danfe was kind enough to remind me that:

WRKSRC= ${WRKDIR}/${PORTNAME}-${PORTVERSION}
is already the default, so for those ports where we are doing:
@${MV} ${WRKDIR}/${PORTNAME} ${WRKSRC}
to avoid the problem of conflicts with the rc.d script of the same
name it is not necessary to define WRKSRC separately.

Clean up this mistake of mine, and standardize for the others.

dns/inadyn/Makefile

@@ -17,7 +17,6 @@ DISTNAME=	${PORTNAME}.v${PORTVERSION}
 MAINTAINER=	samm@os2.kiev.ua
 COMMENT=	INADYN - Simple DYNAMIC DNS client
 
-WRKSRC=		${WRKDIR}/${PORTNAME}-${PORTVERSION}
 USE_RC_SUBR=	inadyn
 USE_ZIP=	yes
 USE_DOS2UNIX=	yes
@@ -33,7 +32,7 @@ PORTDOCS=	readme.html
 PLIST_FILES=	bin/inadyn
 
 post-extract:
-	@${MV} ${WRKDIR}/${PORTNAME} ${WRKDIR}/${PORTNAME}-${PORTVERSION}
+	@${MV} ${WRKDIR}/${PORTNAME} ${WRKSRC}
 
 post-patch:
 	@${REINPLACE_CMD} -e 's|gcc|$$\(CC\)|g' ${WRKSRC}/makefile

games/cave9/Makefile

@@ -22,7 +22,6 @@ DATAVER=	4
 USE_GMAKE=	yes
 USE_SDL=	sdl ttf image
 
-WRKSRC=		${WRKDIR}/${PORTNAME}-${PORTVERSION}
 BUILD_WRKSRC=	${WRKSRC}/src
 
 MAKEFILE=	GNUmakefile
@@ -31,7 +30,7 @@ CFLAGS+=	-DDATADIR=\\\"${DATADIR}\\\"
 PORTDOCS=	*
 
 post-extract:
-	@${MV} ${WRKDIR}/data ${WRKSRC}/
+	@${MV} ${WRKDIR}/data ${WRKSRC}
 
 do-install:
 	${INSTALL_PROGRAM} ${WRKSRC}/cave9 ${PREFIX}/bin

net-mgmt/ng_ipacct/Makefile

@@ -25,7 +25,6 @@ OPTIONS=	MEM_ZONE "Use UMA zone allocator (>= 5.x only)" on
 KMODDIR=	/boot/modules
 PLIST_SUB+=	KMODDIR=${KMODDIR:S!^/!!}
 
-WRKSRC=		${WRKDIR}/${PORTNAME}-${PORTVERSION}
 MAKE_ENV=	BINDIR="${PREFIX}/sbin" KMODDIR=${KMODDIR}
 
 MAN8=		ipacctctl.8

net/rinetd/Makefile

@@ -19,8 +19,6 @@ COMMENT=	A simple TCP port redirector
 
 OPTIONS_DEFINE=	DOCS
 
-WRKSRC=		${WRKDIR}/rinetd-${PORTVERSION}
-
 MAKE_JOBS_SAFE=	yes
 USE_DOS2UNIX=	yes