mail/dot-forward: remove cat files

cat files have been removed from base long ago, brings no values in 2023
while here remove usage of MANPREFIX and move manpages to share/man

mail/dot-forward/Makefile

@@ -1,5 +1,6 @@
 PORTNAME=	dot-forward
 PORTVERSION=	0.71
+PORTREVISION=	1
 CATEGORIES=	mail
 MASTER_SITES=	http://cr.yp.to/software/
 
@@ -12,20 +13,15 @@ USES=		gmake groff
 ALL_TARGET=	default
 
 PLIST_FILES=	bin/dot-forward \
-		man/man1/dot-forward.1.gz \
-		man/cat1/dot-forward.0.gz
+		share/man/man1/dot-forward.1.gz
 
 do-install:
 .for binfile in dot-forward
 	${INSTALL_PROGRAM} ${WRKSRC}/${binfile} ${STAGEDIR}${PREFIX}/bin/${binfile}
 .endfor
 
 .for manfile in dot-forward.1
-	${INSTALL_MAN} ${WRKSRC}/${manfile} ${STAGEDIR}${PREFIX}/man/man1/${manfile}
-.endfor
-
-.for catfile in dot-forward.0
-	${INSTALL_MAN} ${WRKSRC}/${catfile} ${STAGEDIR}${MAN1PREFIX}/man/cat1/${catfile}
+	${INSTALL_MAN} ${WRKSRC}/${manfile} ${STAGEDIR}${PREFIX}/share/man/man1/${manfile}
 .endfor
 
 .include <bsd.port.mk>