rtos: Use lower case filenames

Change-Id: I309c7a649e33f516e28037fef2dc6e574d48c000
Signed-off-by: Marc Schink <dev@zapb.de>
Reviewed-on: https://review.openocd.org/c/openocd/+/8334
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>

src/rtos/Makefile.am

@@ -11,15 +11,15 @@ noinst_LTLIBRARIES += %D%/librtos.la
 	%D%/rtos_ucos_iii_stackings.c \
 	%D%/rtos_riot_stackings.c \
 	%D%/rtos_nuttx_stackings.c \
-	%D%/FreeRTOS.c \
-	%D%/ThreadX.c \
-	%D%/eCos.c \
+	%D%/freertos.c \
+	%D%/threadx.c \
+	%D%/ecos.c \
 	%D%/linux.c \
 	%D%/chibios.c \
 	%D%/chromium-ec.c \
-	%D%/embKernel.c \
+	%D%/embkernel.c \
 	%D%/mqx.c \
-	%D%/uCOS-III.c \
+	%D%/ucos_iii.c \
 	%D%/nuttx.c \
 	%D%/rtkernel.c \
 	%D%/hwthread.c \