dix: check_modmap_change() returns Success, not true

Not sure what if anything calls XSetDeviceModifierMapping() but this would've
failed all the time. check_modmap_change() returns Success but we were
treating it like a boolean. Fix this.

Reported-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Keith Packard <keithp@keithp.com>
(cherry picked from commit 4fe02b8d)

dix/inpututils.c

@@ -282,7 +282,7 @@ change_modmap(ClientPtr client, DeviceIntPtr dev, KeyCode *modkeymap,
     else if (!IsFloating(dev) &&
              GetMaster(dev, MASTER_KEYBOARD)->lastSlave == dev) {
         /* If this fails, expect the results to be weird. */
-        if (check_modmap_change(client, dev->master, modmap))
+        if (check_modmap_change(client, dev->master, modmap) == Success)
             do_modmap_change(client, dev->master, modmap);
     }