stereo call recording support

Patch that allows for call recording in
stereo (left channel: TX; right channel:
RX). Tested on Nexus 5 (MSM8974). Likely
works on other recent MSM chipsets as
well.

Change-Id: I3dd14f99f17106e0e16a8cdb4a951dc8a4aaea63
Merge branch 'cm-11.0' into kk_mkt