ASoC: msm: qdsp6v2: Remove constraints for MI2S interface

MI2S supports programming of serial data line to either Tx
or Rx direction. However, once MI2S is activated, sample
rate and bitwidth on all serial data lines must be the same.
Currently, constraint list is imposed once one direction of
MI2S is started to ensure the other direction is configured
with same sample rate and bitwidth. Unfortunately, it was
found that even though MI2S CPU DAIs are used as back-ends,
the constraint list is also applied on the front-end. This
results in hardware parameter set failure when application
tries to enable front-end PCM device with different hardware
parameter. To avoid this problem, the decision is not to impose
constraint list but simply check for sample rate and bitwidth
on CPU DAI matching other running CPU DAI on the same MI2S.

Change-Id: If7a41c34a271bd9a7f271daa1b70c09e42fc25dd
Signed-off-by: Venkat Sudhir <vsudhir@codeaurora.org>