ASoC: msm: Add MP2 decode support in compress driver

Add MP2 decoder support to ALSA compressed driver. It
allows user-space application to play MP2 audio data through
QDSP6.

Change-Id: I44c35ebe40a361c70bfde3caf88f4f4c6bb457e4
Signed-off-by: Dhananjay Kumar <dhakumar@codeaurora.org>