usb: gadget: imx_udc: 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>

drivers/usb/gadget/imx_udc.c

@@ -1461,15 +1461,10 @@ static int __init imx_udc_probe(struct platform_device *pdev)
 	imx_usb->clk = clk;
 	imx_usb->dev = &pdev->dev;
 
-	device_initialize(&imx_usb->gadget.dev);
-
+	imx_usb->gadget.register_my_device = true;
 	imx_usb->gadget.dev.parent = &pdev->dev;
 	imx_usb->gadget.dev.dma_mask = pdev->dev.dma_mask;
 
-	ret = device_add(&imx_usb->gadget.dev);
-	if (retval)
-		goto fail4;
-
 	platform_set_drvdata(pdev, imx_usb);
 
 	usb_init_data(imx_usb);
@@ -1481,11 +1476,9 @@ static int __init imx_udc_probe(struct platform_device *pdev)
 
 	ret = usb_add_gadget_udc(&pdev->dev, &imx_usb->gadget);
 	if (ret)
-		goto fail5;
+		goto fail4;
 
 	return 0;
-fail5:
-	device_unregister(&imx_usb->gadget.dev);
 fail4:
 	for (i = 0; i < IMX_USB_NB_EP + 1; i++)
 		free_irq(imx_usb->usbd_int[i], imx_usb);
@@ -1509,7 +1502,6 @@ static int __exit imx_udc_remove(struct platform_device *pdev)
 	int i;
 
 	usb_del_gadget_udc(&imx_usb->gadget);
-	device_unregister(&imx_usb->gadget.dev);
 	imx_udc_disable(imx_usb);
 	del_timer(&imx_usb->timer);