bluetooth: Send HCI RESET during BT OFF

While turning BT OFF HCI RESET is not being sent and hence
controller is not in proper state when user does BT OFF
from GUI.

Change-Id: I3375215597cb6c6c45d756596c1abdc60ca643d5
CRs-Fixed: 676608
Signed-off-by: Anantha Krishnan <ananthk@codeaurora.org>
Signed-off-by: Rupesh Tatiya <rtatiya@codeaurora.org>