zathura-ps: fix CFLAGS and LDFLAGS

srcpkgs/zathura-ps/template

@@ -1,7 +1,7 @@
 # Template file for 'zathura-ps'
 pkgname=zathura-ps
 version=0.2.2
-revision=3
+revision=4
 build_style=gnu-makefile
 maintainer="Dominik Honnef <dominik@honnef.co>"
 hostmakedepends="pkg-config"
@@ -12,6 +12,11 @@ short_desc="PostScript support for zathura"
 distfiles="http://pwmt.org/projects/${pkgname}/download/${pkgname}-${version}.tar.gz"
 checksum=e6546261db03b0b6b6499a8e109dc9ff3b8eb8b154ce45f5c6284c1e76d1d7a8
 
+pre_build() {
+	sed -i 's/^\(CFLAGS *+=\)/override \1/' config.mk
+	sed -i 's/^\(LDFLAGS *+=\)/override \1/' config.mk
+}
+
 post_install() {
 	vlicense LICENSE
 }