data/Makefile.am: make --disable-settings actually work
data/Makefile.am: make --disable-settings actually work

Even if ENABLE_SETTINGS was not set, the files were still installed as
@GSETTINGS_RULES@ was still expanded.

https://bugzilla.gnome.org/show_bug.cgi?id=706801

GNOME/telepathy-account-widgets,GNOME/telepathy-account-widgets,Distrotech/telepathy-account-widgets,GNOME/telepathy-account-widgets,Distrotech/telepathy-account-widgets