BT: Multi HF support in libhardware.

This patch adds multi hf support in libhardware.
Adds bd_addr parameter for callbacks from stack.

Conflicts:

	include/hardware/bt_multi_hf.h

Change-Id: I872ba67422ae4310818d7b58ca051085f9146886
Bluetooth: support for a2dp sink

 - support to check remote sep type
 - support to suspend streaming in a2dp sink

CRs-Fixed: 580884

Change-Id: I9355056c663fb0cd685301cc76be6d1a700ee5f1
Bluetooth: A2DP SINK changes for audiofocus

 - manage audio focus
 - send resume_sink from application

CRs-Fixed: 584276

Change-Id: I0eeb06b70b9dbb8c2276b0accb6afbafcba65376