Clean/ignore log directory

Clean out the log directory like the rest, and ignore it in git.

Signed-off-by: Sean Anderson <seanga2@gmail.com>

.gitignore

@@ -5,6 +5,7 @@
 *.json
 *.asc
 *.post.v
+log
 
 # test artifacts
 __pycache__

Makefile

@@ -103,4 +103,5 @@ asc: $(addprefix rtl/,$(addsuffix .asc,$(MODULES)))
 .PHONY: clean
 clean:
 	rm -f *.fst
+	rm -rf log
 	cd rtl && rm -f *.json *.asc *.pre *.vvp *.d *.synth.v *.place.v