Fix pkg-message displaying

PR:		248151
Approved by:	jrm (maintainer)
MFH:		2020Q3

shells/git-prompt.zsh/Makefile

@@ -3,6 +3,7 @@
 PORTNAME=	git-prompt.zsh
 DISTVERSIONPREFIX=	v
 DISTVERSION=	2.3.0
+PORTREVISION=	1
 CATEGORIES=	shells
 
 MAINTAINER=	jrm@FreeBSD.org
@@ -21,6 +22,7 @@ NO_ARCH=	yes
 NO_BUILD=	yes
 PLIST_FILES=	${DATADIR}/${PORTNAME} ${DOCSDIR}/README.md
 SUB_FILES=	pkg-message
+SUB_LIST+=	PORTNAME=${PORTNAME}
 
 do-install:
 	@${MKDIR} ${STAGEDIR}${DATADIR}

shells/git-prompt.zsh/files/pkg-message.in

@@ -6,7 +6,7 @@ Final git-prompt.zsh setup instructions:
 To add the git status indicator to your prompt, source git-prompt.zsh in
 one of your Zsh startup files using
 
-source %%DATADIR%%${PORTNAME}/${PORTNAME}
+source %%DATADIR%%/%%PORTNAME%%
 
 Next, add ' $(gitprompt)%# ' to the end of the PROMPT value like in the
 example below.