fixed A2DP

Change-Id: Icc3df20319877ab963478ceea009c80ac3507bb1
added support for a2dp_tuning kernel tweak

Change-Id: If732b986b1c69dcb936da06027981fda20239d5f
disable a2dp tuning for now - we want this only when playing and not on connecting

Change-Id: I4f428fe6b85b73b967283e8236986958fae4e0c7