Input: xpad - enable force feedback on xbox 360 controllers only

Commit 4994cd8dadcf9d484ab3ec19f3c7c7a4e5353c1c introduced a
regression which causes xpad to report force feedback cababilities
for non-360 controllers too, even while there is no actual support
for those.

Fix that by adding a check for XTYPE_XBOX360 to xpad_init_ff().

Signed-off-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/input/joystick/xpad.c

@@ -499,6 +499,9 @@ static int xpad_play_effect(struct input_dev *dev, void *data,
 
 static int xpad_init_ff(struct usb_xpad *xpad)
 {
+	if (xpad->xtype != XTYPE_XBOX360)
+		return 0;
+
 	input_set_capability(xpad->dev, EV_FF, FF_RUMBLE);
 
 	return input_ff_create_memless(xpad->dev, NULL, xpad_play_effect);