ASoC: msm: qdsp6v2: Fix input and output channel mapping

For multichannel playback, fix default input and output channel
map to the ch mixer and add compressed driver mixer ctl to
receive the input stream channel map

Change-Id: I56d4da70274625304ba21a10b588d2f0869ca667
Signed-off-by: Alexy Joseph <alexyj@codeaurora.org>