ASoC: msm: Add support to enable SRS feature on DSP

Add new mixer controls for setting SRS parameters which
enables SRS on DSP. Add required structures and commands
for enabling SRS

Change-Id: Ife0c8223c534dd3daad10dd5fec18630da732611
Signed-off-by: Sriranjan Srikantam <cssrika@codeaurora.org>

Conflicts:

	include/sound/apr_audio.h
	sound/soc/msm/msm-pcm-routing.c