usb: gadget: at91_udc: Propagate devicetree to gadget drivers

Fill dev.of_node of gadget drivers, so they can use devicetree
Signed-off-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/at91_udc.c

@@ -1634,6 +1634,7 @@ static int at91_start(struct usb_gadget *gadget,
 	udc = container_of(gadget, struct at91_udc, gadget);
 	udc->driver = driver;
 	udc->gadget.dev.driver = &driver->driver;
+	udc->gadget.dev.of_node = udc->pdev->dev.of_node;
 	dev_set_drvdata(&udc->gadget.dev, &driver->driver);
 	udc->enabled = 1;
 	udc->selfpowered = 1;