Bluetooth: btmrvl: Remove empty destruct cb

The callback is optional and we provide an empty callback so remove it
entirely.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

drivers/bluetooth/btmrvl_main.c

@@ -387,10 +387,6 @@ static int btmrvl_ioctl(struct hci_dev *hdev,
 	return -ENOIOCTLCMD;
 }
 
-static void btmrvl_destruct(struct hci_dev *hdev)
-{
-}
-
 static int btmrvl_send_frame(struct sk_buff *skb)
 {
 	struct hci_dev *hdev = (struct hci_dev *) skb->dev;
@@ -553,7 +549,6 @@ int btmrvl_register_hdev(struct btmrvl_private *priv)
 	hdev->close = btmrvl_close;
 	hdev->flush = btmrvl_flush;
 	hdev->send = btmrvl_send_frame;
-	hdev->destruct = btmrvl_destruct;
 	hdev->ioctl = btmrvl_ioctl;
 	hdev->owner = THIS_MODULE;