usb: gadget: fusb300_udc: should not call gadget driver's .unbind

It has already been covered by udc core
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/fusb300_udc.c

@@ -1325,8 +1325,6 @@ static int fusb300_udc_stop(struct usb_gadget *g,
 {
 	struct fusb300 *fusb300 = to_fusb300(g);
 
-	driver->unbind(&fusb300->gadget);
-
 	init_controller(fusb300);
 	fusb300->driver = NULL;