build: Fix on OpenBSD. TIL awk.

GNUmakefile

@@ -3,7 +3,7 @@
 MAKEFLAGS += --warn-undefined-variables
 MAKEFLAGS += --no-builtin-rules
 
-## == Tilde Friends makefile build. ==
+## == Tilde Friends build. ==
 ##
 ## This is a list of all supported build targets.
 ##
@@ -1245,9 +1245,12 @@ clean: ## Clean all generated files from the out/ directory.
 ## Documentation:
 ##
 help: ## Display this help message.
-	@awk -F: ' \
-	/^##/ { sub(/^##\s?/, ""); print $$0 } \
-	/^\w+: .*##/ { sub(/^/, ""); sub(/:.*##\s?/, ":"); printf "%-32s %s\n", $$1, $$2 } \
+	@awk \
+	-F: \
+	-vG=$$(tput setaf 2) \
+	-vR=$$(tput sgr0) ' \
+	/^##/ { sub(/^##\s?/, ""); printf "%s%s%s\n", G, $$0, R } \
+	/^[[:alnum:]-]+:.*##/ { sub(/:.*##\s?/, ":"); printf "%s%-20s%s %s\n", G, $$1, R, $$2 } \
 	' < $(filter-out %.d,$(MAKEFILE_LIST))
 	@echo "" # Blank line.
 .PHONY: help