ASoC: msm: Add new audio calibration driver

New msm_audio_cal calibration driver acts as a
routing driver which routes calibration from
user space to the appropriate kernel client.
Kernel clients register callbacks with the
calibration driver and are notified of changes
made by user space.

Change-Id: I0e4499c1c67dc45ca44340fa700fd03929dbcc44
Signed-off-by: Ben Romberger <bromberg@codeaurora.org>