plugins: add 'commit' target to ease a bit of typing

Mk/plugins.mk

@@ -280,6 +280,9 @@ WRKDIR?=${.CURDIR}/work
 WRKSRC?=${WRKDIR}/src
 PKGDIR?=${WRKDIR}/pkg
 
+ensure-workdirs:
+	@mkdir -p ${WRKSRC} ${PKGDIR}
+
 package: check
 	@rm -rf ${WRKSRC}
 	@mkdir -p ${WRKSRC} ${PKGDIR}
@@ -455,4 +458,8 @@ test: check
 		    ${.CURDIR}/src/opnsense/mvc/tests; \
 	fi
 
+commit: ensure-workdirs
+	@echo -n "${.CURDIR:C/\// /g:[-2]}/${.CURDIR:C/\// /g:[-1]}: " > \
+	    ${WRKDIR}/.commitmsg && git commit -eF ${WRKDIR}/.commitmsg .
+
 .PHONY:	check plist-fix