gio-querymodules: Ensure we're linked to GObject

Since we're dynamically loading objects, after the g_type_init()
change, we now need to ensure people building with --as-needed don't
lose the DT_NEEDED on libgobject.

https://bugzilla.gnome.org/show_bug.cgi?id=691077

gio/gio-querymodules.c

@@ -136,6 +136,9 @@ main (gint   argc,
       return 1;
     }
 
+  /* Be defensive and ensure we're linked to GObject */
+  g_type_ensure (G_TYPE_OBJECT);
+
   for (i = 1; i < argc; i++)
     query_dir (argv[i]);