misc: Added a clang-tidy Makefile target so enforcing the formatting is easier

Makefile

@@ -33,4 +33,7 @@ endif
 clang-tidy:
 	$(Q)scripts/run-clang-tidy.py -s "$(PWD)"
 
-.PHONY: clean all_platforms clang-tidy
+clang-format:
+	$(Q)$(MAKE) $(MFLAGS) -C src $@
+
+.PHONY: clean all_platforms clang-tidy clang-format

src/Makefile

@@ -128,7 +128,7 @@ ifndef PC_HOSTED
 	$(Q)$(OBJCOPY) -O ihex $^ $@
 endif
 
-.PHONY:	clean host_clean all_platforms FORCE
+.PHONY:	clean host_clean all_platforms clang-format FORCE
 
 clean:	host_clean
 	$(Q)echo "  CLEAN"
@@ -191,4 +191,7 @@ else
 	fi
 endif
 
+clang-format:
+	$(Q)clang-format -i *.c */*.c */*/*.c *.h */*.h */*/*.h
+
 -include *.d