dev-libs/appstream: Fix build with USE !test

Closes: https://bugs.gentoo.org/675944
Package-Manager: Portage-2.3.58, Repoman-2.3.12
Signed-off-by: Andreas Sturmlechner <asturm@gentoo.org>

dev-libs/appstream/appstream-0.12.4.ebuild

@@ -47,6 +47,9 @@ RDEPEND="${DEPEND}"
 src_prepare() {
 	default
 	sed -e "/^as_doc_target_dir/s/appstream/${PF}/" -i docs/meson.build || die
+	if ! use test; then
+		sed -e "/^subdir.*tests/s/^/#DONT /" -i {,qt/}meson.build || die # bug 675944
+	fi
 }
 
 src_configure() {