use inline bash instead

less/Makefile

@@ -1,9 +1,7 @@
 CSSDIR=../static/css/
 
 all :
-ifeq (,$(shell command -v lessc 2> /dev/null))
+	@command -v lessc >/dev/null 2>&1 || { echo >&2 "less is not installed, please run install-less.sh."; exit 1; }
-$(error "less is not installed, please run install-less.sh")
-endif
 	lessc app.less --clean-css="--s1 --advanced" $(CSSDIR)write.css
 	lessc fonts.less --clean-css="--s1 --advanced" $(CSSDIR)fonts.css
 	lessc icons.less --clean-css="--s1 --advanced" $(CSSDIR)icons.css