ASoC: msm: send gain info for all channels mask

- currently gain is added for only number of channels and clip
  channel count is send to dsp.
- but it is possible that channel mask that driver has is different
  than what dsp discovers after decoding the codec config data
- volume will not be applied to channels that differ between driver
  and dsp and device volume will not apply on these channels
- change is to control multi-channel volume using master gain

Change-Id: Icd8ca4e935d9095dd9ef8b65eff34629326fb563
Signed-off-by: vivek mehta <mvivek@codeaurora.org>