Make 'make makefiles' give an error message less often. r=cls

config/rules.mk

@@ -613,7 +613,7 @@ makefiles: $(SUBMAKEFILES)
 ifdef DIRS
 	@for d in $(filter-out $(STATIC_MAKEFILES), $(DIRS)); do\
 		$(UPDATE_TITLE) 				\
-		$(MAKE) -C $$d $@				\
+		$(MAKE) -C $$d $@;				\
 	done
 endif