README: Use proper Markdown syntax

The README file contains a mixture of Markdown and non-Markdown syntax.
Refurbish the document and use only Markdown syntax according to the
specification in [1].

[1] https://www.markdownguide.org/

Change-Id: If58f4e2971dc798a03a78841226804ab1f2d33c8
Signed-off-by: Marc Schink <dev@zapb.de>
Reviewed-on: https://review.openocd.org/c/openocd/+/8387
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
Tested-by: jenkins

README

@@ -1,5 +1,4 @@
-Welcome to OpenOCD!
+# Welcome to OpenOCD!
-===================
 
 OpenOCD provides on-chip programming and debugging support with a
 layered architecture of JTAG interface and TAP support including:
@@ -26,33 +25,33 @@ This README file contains an overview of the following topics:
 - packaging tips.
 
 
-============================
+# Quickstart for the impatient
-Quickstart for the impatient
-============================
 
 If you have a popular board then just start OpenOCD with its config,
 e.g.:
 
-  openocd -f board/stm32f4discovery.cfg
+    openocd -f board/stm32f4discovery.cfg
 
 If you are connecting a particular adapter with some specific target,
 you need to source both the jtag interface and the target configs,
 e.g.:
 
-  openocd -f interface/ftdi/jtagkey2.cfg -c "transport select jtag" \
+```
-          -f target/ti_calypso.cfg
+openocd -f interface/ftdi/jtagkey2.cfg -c "transport select jtag" \
+        -f target/ti_calypso.cfg
+```
 
-  openocd -f interface/stlink.cfg -c "transport select hla_swd" \
+```
-          -f target/stm32l0.cfg
+openocd -f interface/stlink.cfg -c "transport select hla_swd" \
+        -f target/stm32l0.cfg
+```
 
 After OpenOCD startup, connect GDB with
 
-  (gdb) target extended-remote localhost:3333
+    (gdb) target extended-remote localhost:3333
 
 
-=====================
+# OpenOCD Documentation
-OpenOCD Documentation
-=====================
 
 In addition to the in-tree documentation, the latest manuals may be
 viewed online at the following URLs:
@@ -71,35 +70,34 @@ by subscribing to the OpenOCD developer mailing list:
 
 	openocd-devel@lists.sourceforge.net
 
-Building the OpenOCD Documentation
+## Building the OpenOCD Documentation
-----------------------------------
 
 By default the OpenOCD build process prepares documentation in the
-"Info format" and installs it the standard way, so that "info openocd"
+"Info format" and installs it the standard way, so that `info openocd`
 can access it.
 
 Additionally, the OpenOCD User's Guide can be produced in the
 following different formats:
 
-  # If PDFVIEWER is set, this creates and views the PDF User Guide.
+If `PDFVIEWER` is set, this creates and views the PDF User Guide.
-  make pdf && ${PDFVIEWER} doc/openocd.pdf
 
-  # If HTMLVIEWER is set, this creates and views the HTML User Guide.
+    make pdf && ${PDFVIEWER} doc/openocd.pdf
-  make html && ${HTMLVIEWER} doc/openocd.html/index.html
+
+If `HTMLVIEWER` is set, this creates and views the HTML User Guide.
+
+    make html && ${HTMLVIEWER} doc/openocd.html/index.html
 
 The OpenOCD Developer Manual contains information about the internal
 architecture and other details about the code:
 
-  # NB! make sure doxygen is installed, type doxygen --version
+Note: make sure doxygen is installed, type doxygen --version
-  make doxygen && ${HTMLVIEWER} doxygen/index.html
+
+    make doxygen && ${HTMLVIEWER} doxygen/index.html
 
 
-==================
+# Supported hardware
-Supported hardware
-==================
 
-JTAG adapters
+## JTAG adapters
--------------
 
 AM335x, ARM-JTAG-EW, ARM-USB-OCD, ARM-USB-TINY, AT91RM9200, axm0432, BCM2835,
 Bus Blaster, Buspirate, Cadence DPI, Cadence vdebug, Chameleon, CMSIS-DAP,
@@ -116,8 +114,7 @@ sysfsgpio, Tigard, TI XDS110, TUMPA, Turtelizer, ULINK, USB-A9260, USB-Blaster,
 USB-JTAG, USBprog, VPACLink, VSLLink, Wiggler, XDS100v2, Xilinx XVC/PCIe,
 Xverve.
 
-Debug targets
+## Debug targets
--------------
 
 ARM: AArch64, ARM11, ARM7, ARM9, Cortex-A/R (v7-A/R), Cortex-M (ARMv{6/7/8}-M),
 FA526, Feroceon/Dragonite, XScale.
@@ -125,8 +122,7 @@ ARCv2, AVR32, DSP563xx, DSP5680xx, EnSilica eSi-RISC, EJTAG (MIPS32, MIPS64),
 ESP32, ESP32-S2, ESP32-S3, Intel Quark, LS102x-SAP, RISC-V, ST STM8,
 Xtensa.
 
-Flash drivers
+## Flash drivers
--------------
 
 ADUC702x, AT91SAM, AT91SAM9 (NAND), ATH79, ATmega128RFA1, Atmel SAM, AVR, CFI,
 DSP5680xx, EFM32, EM357, eSi-RISC, eSi-TSMC, EZR32HG, FM3, FM4, Freedom E SPI,
@@ -140,12 +136,9 @@ TI CC13xx, TI CC26xx, TI CC32xx, TI MSP432, Winner Micro w600, Xilinx XCF,
 XMC1xxx, XMC4xxx.
 
 
-==================
+# Installing OpenOCD
-Installing OpenOCD
-==================
 
-A Note to OpenOCD Users
+## A Note to OpenOCD Users
------------------------
 
 If you would rather be working "with" OpenOCD rather than "on" it, your
 operating system or JTAG interface supplier may provide binaries for
@@ -164,8 +157,7 @@ Users of these binary versions of OpenOCD must contact their Packager to
 ask for support or newer versions of the binaries; the OpenOCD
 developers do not support packages directly.
 
-A Note to OpenOCD Packagers
+## A Note to OpenOCD Packagers
----------------------------
 
 You are a PACKAGER of OpenOCD if you:
 
@@ -192,11 +184,9 @@ suggestions:
 - Use "ftdi" interface adapter driver for the FTDI-based devices.
 
 
-================
+# Building OpenOCD
-Building OpenOCD
-================
 
-The INSTALL file contains generic instructions for running 'configure'
+The INSTALL file contains generic instructions for running `configure`
 and compiling the OpenOCD source code. That file is provided by
 default for all GNU autotools packages. If you are not familiar with
 the GNU autotools, then you should read those instructions first.
@@ -204,8 +194,7 @@ the GNU autotools, then you should read those instructions first.
 The remainder of this document tries to provide some instructions for
 those looking for a quick-install.
 
-OpenOCD Dependencies
+## OpenOCD Dependencies
---------------------
 
 GCC or Clang is currently required to build OpenOCD. The developers
 have begun to enforce strict code warnings (-Wall, -Werror, -Wextra,
@@ -250,8 +239,7 @@ Optional development script checkpatch needs:
 - python
 - python-ply
 
-Permissions delegation
+## Permissions delegation
-----------------------
 
 Running OpenOCD with root/administrative permissions is strongly
 discouraged for security reasons.
@@ -268,89 +256,81 @@ For parport adapters on Windows you need to run install_giveio.bat
 (it's also possible to use "ioperm" with Cygwin instead) to give
 ordinary users permissions for accessing the "LPT" registers directly.
 
-Compiling OpenOCD
+## Compiling OpenOCD
------------------
 
 To build OpenOCD, use the following sequence of commands:
 
-  ./bootstrap (when building from the git repository)
+    ./bootstrap
-  ./configure [options]
+    ./configure [options]
-  make
+    make
-  sudo make install
+    sudo make install
 
-The 'configure' step generates the Makefiles required to build
+The `bootstrap` command is only necessary when building from the Git repository. The `configure` step generates the Makefiles required to build
 OpenOCD, usually with one or more options provided to it. The first
 'make' step will build OpenOCD and place the final executable in
-'./src/'. The final (optional) step, ``make install'', places all of
+'./src/'. The final (optional) step, `make install`, places all of
 the files in the required location.
 
-To see the list of all the supported options, run
+To see the list of all the supported options, run `./configure --help`
-  ./configure --help
 
-Cross-compiling Options
+## Cross-compiling Options
------------------------
 
 Cross-compiling is supported the standard autotools way, you just need
 to specify the cross-compiling target triplet in the --host option,
 e.g. for cross-building for Windows 32-bit with MinGW on Debian:
 
-  ./configure --host=i686-w64-mingw32 [options]
+    ./configure --host=i686-w64-mingw32 [options]
 
 To make pkg-config work nicely for cross-compiling, you might need an
 additional wrapper script as described at
 
-  https://autotools.io/pkgconfig/cross-compiling.html
+    https://autotools.io/pkgconfig/cross-compiling.html
 
 This is needed to tell pkg-config where to look for the target
 libraries that OpenOCD depends on. Alternatively, you can specify
-*_CFLAGS and *_LIBS environment variables directly, see "./configure
+`*_CFLAGS` and `*_LIBS` environment variables directly, see `./configure
---help" for the details.
+--help` for the details.
 
 For a more or less complete script that does all this for you, see
 
-  contrib/cross-build.sh
+    contrib/cross-build.sh
 
-Parallel Port Dongles
+## Parallel Port Dongles
----------------------
 
 If you want to access the parallel port using the PPDEV interface you
-have to specify both --enable-parport AND --enable-parport-ppdev, since
+have to specify both `--enable-parport` and `--enable-parport-ppdev`, since
 the later option is an option to the parport driver.
 
-The same is true for the --enable-parport-giveio option, you have to
+The same is true for the `--enable-parport-giveio` option, you have to
-use both the --enable-parport AND the --enable-parport-giveio option
+use both the `--enable-parport` and the `--enable-parport-giveio` option
 if you want to use giveio instead of ioperm parallel port access
 method.
 
 
-==========================
+# Obtaining OpenOCD From GIT
-Obtaining OpenOCD From GIT
-==========================
 
 You can download the current GIT version with a GIT client of your
 choice from the main repository:
 
-   git://git.code.sf.net/p/openocd/code
+    git://git.code.sf.net/p/openocd/code
 
 You may prefer to use a mirror:
 
-   http://repo.or.cz/r/openocd.git
+    http://repo.or.cz/r/openocd.git
-   git://repo.or.cz/openocd.git
+    git://repo.or.cz/openocd.git
 
 Using the GIT command line client, you might use the following command
 to set up a local copy of the current repository (make sure there is no
 directory called "openocd" in the current directory):
 
-   git clone git://git.code.sf.net/p/openocd/code openocd
+    git clone git://git.code.sf.net/p/openocd/code openocd
 
-Then you can update that at your convenience using
+Then you can update that at your convenience using `git pull`.
-
-   git pull
 
 There is also a gitweb interface, which you can use either to browse
 the repository or to download arbitrary snapshots using HTTP:
 
-   http://repo.or.cz/w/openocd.git
+    http://repo.or.cz/w/openocd.git
 
 Snapshots are compressed tarballs of the source tree, about 1.3 MBytes
 each at this writing.