Bluetooth: Queue adv_work on system workqueue

This patch queues hdev->adv_work on the system-wide workqueue
instead of on hdev->workqueue. This way we keep only tx/rx works
on hdev->workqueue.
Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

net/bluetooth/hci_event.c

@@ -1054,8 +1054,7 @@ static void hci_cc_le_set_scan_enable(struct hci_dev *hdev,
 	case LE_SCANNING_DISABLED:
 		clear_bit(HCI_LE_SCAN, &hdev->dev_flags);
 
-		queue_delayed_work(hdev->workqueue, &hdev->adv_work,
-							ADV_CLEAR_TIMEOUT);
+		schedule_delayed_work(&hdev->adv_work, ADV_CLEAR_TIMEOUT);
 		break;
 
 	default: