Add a mechanism for Audio Feeding Parameters negotiation

Previously, the Audio Feeding Parameters between the Media Framework
and A2DP were hard-coded: 44.1 KHz sample rate, 16-bits per sample, Stereo.
Now the Media Framework queries A2DP, and uses the returned values.

Bug: b/30958229
Test: Manual testing: A2DP streaming to headphones. TestTracker/68727
Change-Id: Ib86035814c49f773b7ed3d64da334ca9ea87eb14