usb: udc: core: fix error handling

The udc device needs to be deleted if error occurs

Fixes: 855ed04a ("usb: gadget: udc-core: independent registration of
	gadgets and gadget drivers")
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/udc/core.c

@@ -1145,7 +1145,7 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
 			if (ret != -EPROBE_DEFER)
 				list_del(&driver->pending);
 			if (ret)
-				goto err4;
+				goto err5;
 			break;
 		}
 	}
@@ -1154,6 +1154,9 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
 
 	return 0;
 
+err5:
+	device_del(&udc->dev);
+
 err4:
 	list_del(&udc->list);
 	mutex_unlock(&udc_lock);