Bluetooth: Support  HFP Client role on Bluedroid.

Implementation of HFP Client role on
Bluedroid stack. Include HFP Client Interface ID.

Change-Id: Ib440099de75081b2bd8d5f01f4d9d1bb467294ea
Merge branch 'cm-10.2' of https://github.com/CyanogenMod/android_hardware_libhardware into jb-mr2