usb: renesas_usbhs: gadget: let udc-core manage gadget->dev

By simply setting a flag, we can drop some
boilerplate code.

Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/renesas_usbhs/mod_gadget.c b/drivers/usb/renesas_usbhs/mod_gadget.c
index 78fca97..5d5fab0 100644
--- a/drivers/usb/renesas_usbhs/mod_gadget.c
+++ b/drivers/usb/renesas_usbhs/mod_gadget.c
@@ -976,15 +976,12 @@
 	/*
 	 * init gadget
 	 */
-	dev_set_name(&gpriv->gadget.dev, "gadget");
 	gpriv->gadget.dev.parent	= dev;
 	gpriv->gadget.dev.release	= usbhs_mod_gadget_release;
 	gpriv->gadget.name		= "renesas_usbhs_udc";
 	gpriv->gadget.ops		= &usbhsg_gadget_ops;
 	gpriv->gadget.max_speed		= USB_SPEED_HIGH;
-	ret = device_register(&gpriv->gadget.dev);
-	if (ret < 0)
-		goto err_add_udc;
+	gpriv->gadget.register_my_device = true;
 
 	INIT_LIST_HEAD(&gpriv->gadget.ep_list);
 
@@ -1014,15 +1011,13 @@
 
 	ret = usb_add_gadget_udc(dev, &gpriv->gadget);
 	if (ret)
-		goto err_register;
+		goto err_add_udc;
 
 
 	dev_info(dev, "gadget probed\n");
 
 	return 0;
 
-err_register:
-	device_unregister(&gpriv->gadget.dev);
 err_add_udc:
 	kfree(gpriv->uep);
 
@@ -1038,8 +1033,6 @@
 
 	usb_del_gadget_udc(&gpriv->gadget);
 
-	device_unregister(&gpriv->gadget.dev);
-
 	kfree(gpriv->uep);
 	kfree(gpriv);
 }