usb: gadget: mv_udc_core: 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/gadget/mv_udc_core.c b/drivers/usb/gadget/mv_udc_core.c
index c8cf959..a7afdfb 100644
--- a/drivers/usb/gadget/mv_udc_core.c
+++ b/drivers/usb/gadget/mv_udc_core.c
@@ -2138,8 +2138,6 @@
 
 	mv_udc_disable(udc);
 
-	device_unregister(&udc->gadget.dev);
-
 	/* free dev, wait for the release() finished */
 	wait_for_completion(udc->done);
 
@@ -2311,15 +2309,11 @@
 	udc->gadget.max_speed = USB_SPEED_HIGH;	/* support dual speed */
 
 	/* the "gadget" abstracts/virtualizes the controller */
-	dev_set_name(&udc->gadget.dev, "gadget");
 	udc->gadget.dev.parent = &pdev->dev;
 	udc->gadget.dev.dma_mask = pdev->dev.dma_mask;
 	udc->gadget.dev.release = gadget_release;
 	udc->gadget.name = driver_name;		/* gadget name */
-
-	retval = device_register(&udc->gadget.dev);
-	if (retval)
-		goto err_destroy_dma;
+	udc->gadget.register_my_device = true;
 
 	eps_init(udc);
 
@@ -2342,7 +2336,7 @@
 		if (!udc->qwork) {
 			dev_err(&pdev->dev, "cannot create workqueue\n");
 			retval = -ENOMEM;
-			goto err_unregister;
+			goto err_destroy_dma;
 		}
 
 		INIT_WORK(&udc->vbus_work, mv_udc_vbus_work);
@@ -2370,8 +2364,6 @@
 
 err_create_workqueue:
 	destroy_workqueue(udc->qwork);
-err_unregister:
-	device_unregister(&udc->gadget.dev);
 err_destroy_dma:
 	dma_pool_destroy(udc->dtd_pool);
 err_free_dma: