bluedroid: Fix build with gcc 4.8

Change-Id: Iaf208370caa59266b959d4d68300706714fd3d5d
increase read buffer size
fixes compatibility issues with ti-hci driver
Remove bluedroid configuration warning

This warning is fired on every full-eng build.  It seems excessive
given that there are very few other warning fired on a full-eng build
and 0 seems like a reasonable goal to shoot for.

Change-Id: I2fb2b5342dee35b3ed05343466309f6c335022ef
Fixed i2s call for headsets

Credits: maxell

Change-Id: I1bdf2ff5e8c475907aa8450af85116bafadd739d