Bluetooth: hci_nokia: Use new hci_uart_unregister_device() function

Simplify _remove() path for hci_nokia.c

Signed-off-by: Ian Molton <ian@mnementh.co.uk>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabor.co.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

drivers/bluetooth/hci_nokia.c

@@ -767,16 +767,8 @@ static int nokia_bluetooth_serdev_probe(struct serdev_device *serdev)
 static void nokia_bluetooth_serdev_remove(struct serdev_device *serdev)
 {
 	struct nokia_bt_dev *btdev = serdev_device_get_drvdata(serdev);
-	struct hci_uart *hu = &btdev->hu;
-	struct hci_dev *hdev = hu->hdev;
 
-
-	hci_unregister_dev(hdev);
-	hci_free_dev(hdev);
-
-	cancel_work_sync(&hu->write_work);
-
-	hu->proto->close(hu);
+	hci_uart_unregister_device(&btdev->hu);
 }
 
 static int nokia_bluetooth_runtime_suspend(struct device *dev)