dix: compare the grab type, not the tempGrab type

No functional change. To get here, GrabMatchesSecond() needs to be TRUE and
for that the two grab types must be identical.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Reviewed-by: Chase Douglas <chase.douglas@canonical.com>

dix/events.c

@@ -3816,7 +3816,7 @@ CheckPassiveGrab(DeviceIntPtr device, GrabPtr grab, InternalEvent *event,
            Since XGrabDeviceButton requires to specify the
            modifierDevice explicitly, we don't override this choice.
          */
-        if (tempGrab->type < GenericEvent)
+        if (grab->type < GenericEvent)
         {
             grab->device = device;
             grab->modifierDevice = GetMaster(device, MASTER_KEYBOARD);