cairo-util: Clean up more Cairo detritus; almost all of it

Pango, Cairo, and fontconfig, all want to leave thread-global data
hanging around in order to maintain a cache. Try to clean up as much of
it as we possibly can on exit, apart from the Pango language string
which appears to be unfreeable, so has been added to LSan suppressions.

Signed-off-by: Daniel Stone <daniels@collabora.com>

clients/window.c

@@ -6063,6 +6063,7 @@ display_destroy(struct display *display)
 		theme_destroy(display->theme);
 	destroy_cursors(display);
 
+	cleanup_after_cairo();
 
 	if (display->relative_pointer_manager)
 		zwp_relative_pointer_manager_v1_destroy(display->relative_pointer_manager);