Blacklist the xdg-app AppStream data as the correct data is added manually
Blacklist the xdg-app AppStream data as the correct data is added manually

We don't want to process both files at startup.

hughsie/appstream-glib,ikeydoherty/appstream-glib,ikeydoherty/appstream-glib,hughsie/appstream-glib,ximion/appstream-glib,hughsie/appstream-glib,ximion/appstream-glib,ximion/appstream-glib