Bluetooth: move power_off to system workqueue

hdev->workqueue will be only for for rx/tx/cmd processing, all other small
works should go to the system workqueue for now.

Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index ad4817c..f4af6593 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -417,7 +417,7 @@
 	if (cp->val)
 		queue_work(hdev->workqueue, &hdev->power_on);
 	else
-		queue_work(hdev->workqueue, &hdev->power_off.work);
+		schedule_work(&hdev->power_off.work);
 
 	err = 0;