BT: Multi HF support in Settings App.

1. The connected sinks are not disconnected from
HeadsetProfile when new sink is connecting.
2. Also return correct connection status for
specific HS.
3. Sets priority for specific HS while disconnecting.

Change-Id: I876f9810be82482cb360451343e4eb2a9f3ed668
Merge remote-tracking branch 'settings/kitkat-remix' into remix-legacy