Bluetooth: Handle CHLD cmd properly incase of Held call

This change will handle the CHLD command properly incase of
Incomming call when there is already active Held call.

Change-Id: Iccb059d71fafb6f4fa3195b8393b8462e4bcff32
CRs-Fixed: 594671
Bluetooth: Create IBluetoothDsdaService.

This change creates IBluetoothDsdaService in
Telephony app which BluetoothPhoneService
will use to communicate DSDA call state changes.

CRs-Fixed: 545484
Change-Id: Ife17935a68114a016dd81aad996716bf7600dac3

Conflicts:
	Android.mk
BT: Multi HF support for BluetoothManager in Telephony.

This patch adds multi hf support in Telephony.
Returns AudioOn state and Connection state for
specific HS.

Change-Id: I1d19111bbf9728675800e356e8bd7652006e2e59