Bluetooth: Skip the shutdown routine if the interface is not up

Most likely, the shutdown routine requires the interface to be up.
This is the case for BTUSB_INTEL: the routine tries to send a command
to the interface, but since this one is down, it fails and exits once
HCI_INIT_TIMEOUT has expired.

Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.0.x

net/bluetooth/hci_core.c

@@ -1557,7 +1557,8 @@ static int hci_dev_do_close(struct hci_dev *hdev)
 {
 	BT_DBG("%s %p", hdev->name, hdev);
 
-	if (!hci_dev_test_flag(hdev, HCI_UNREGISTER)) {
+	if (!hci_dev_test_flag(hdev, HCI_UNREGISTER) &&
+	    test_bit(HCI_UP, &hdev->flags)) {
 		/* Execute vendor specific shutdown routine */
 		if (hdev->shutdown)
 			hdev->shutdown(hdev);