[gnome-mahjongg] Do not forget to install appdata

[Robert Roth <robertroth src gnome org>]

commit 39a7e8b2de48b7cf92fb31f63667c27d405dbe52
Author: Robert Roth <robert roth off gmail com>
Date:   Mon Feb 5 20:43:35 2018 +0200

    Do not forget to install appdata

 data/Makefile.am |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/data/Makefile.am b/data/Makefile.am
index c243111..9ed8775 100644
--- a/data/Makefile.am
+++ b/data/Makefile.am
@@ -24,6 +24,7 @@ $(desktop_DATA): $(desktop_in_files)
 
 appstream_in_files = gnome-mahjongg.appdata.xml.in
 appstream_XML = $(appstream_in_files:.xml.in=.xml)
+@APPSTREAM_XML_RULES@
 $(appstream_XML): $(appstream_in_files)
                $(AM_V_GEN)$(MSGFMT) --xml --template $< -d $(top_srcdir)/po -o $@