usb: gadget: at91_udc: remove driver_data direct access of struct device

In the near future, the driver core is going to not allow direct access
to the driver_data pointer in struct device.  Instead, the functions
dev_get_drvdata() and dev_set_drvdata() should be used.  These functions
have been around since the beginning, so are backwards compatible with
all older kernel versions.

Cc: linux-usb@vger.kernel.org
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/at91_udc.c

@@ -1574,7 +1574,7 @@ int usb_gadget_register_driver (struct usb_gadget_driver *driver)
 
 	udc->driver = driver;
 	udc->gadget.dev.driver = &driver->driver;
-	udc->gadget.dev.driver_data = &driver->driver;
+	dev_set_drvdata(&udc->gadget.dev, &driver->driver);
 	udc->enabled = 1;
 	udc->selfpowered = 1;
 
@@ -1583,7 +1583,7 @@ int usb_gadget_register_driver (struct usb_gadget_driver *driver)
 		DBG("driver->bind() returned %d\n", retval);
 		udc->driver = NULL;
 		udc->gadget.dev.driver = NULL;
-		udc->gadget.dev.driver_data = NULL;
+		dev_set_drvdata(&udc->gadget.dev, NULL);
 		udc->enabled = 0;
 		udc->selfpowered = 0;
 		return retval;
@@ -1613,7 +1613,7 @@ int usb_gadget_unregister_driver (struct usb_gadget_driver *driver)
 
 	driver->unbind(&udc->gadget);
 	udc->gadget.dev.driver = NULL;
-	udc->gadget.dev.driver_data = NULL;
+	dev_set_drvdata(&udc->gadget.dev, NULL);
 	udc->driver = NULL;
 
 	DBG("unbound from %s\n", driver->driver.name);