usb : gadget : fsl: fix the fault issue on rmmod

completion in udc_controller->done should be assign with proper
value before complete called. The complete called in fsl_udc_release
which intern called from usb_del_gadget_udc, so moving assignment
before calling usb_del_gadget_udc

Signed-off-by: Suresh Gupta <suresh.gupta@freescale.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/fsl_udc_core.c

@@ -2532,8 +2532,8 @@ static int __exit fsl_udc_remove(struct platform_device *pdev)
 	if (!udc_controller)
 		return -ENODEV;
 
-	usb_del_gadget_udc(&udc_controller->gadget);
 	udc_controller->done = &done;
+	usb_del_gadget_udc(&udc_controller->gadget);
 
 	fsl_udc_clk_release();