$NetBSD$

Fix the invalid DESTDIR path containing '/usr' and use the
pkgsrc macros.

--- vxp2ps/Makefile.orig	2021-01-19 08:35:54.000000000 +0000
+++ vxp2ps/Makefile
@@ -12,7 +12,10 @@ vxp2dkw: vxp2dkw.c
 	gcc vxp2dkw.c -o vxp2dkw -lm
 
 install: all
-	install -c -s vxp2ps vxp2tex vxp2dkw "$(DESTDIR)"/usr/bin
+	${BSD_INSTALL_PROGRAM_DIR} ${DESTDIR}${PREFIX}/bin
+	${BSD_INSTALL_PROGRAM} vxp2ps ${DESTDIR}${PREFIX}/bin
+	${BSD_INSTALL_PROGRAM} vxp2tex ${DESTDIR}${PREFIX}/bin
+	${BSD_INSTALL_PROGRAM} vxp2dkw ${DESTDIR}${PREFIX}/bin
 
 clean:
 	rm -f core *~ vxp2ps vxp2tex vxp2dkw
