ASoC: msm: constify snd_pcm_ops structures for MSM platforms

Check for snd_pcm_ops structures that are only stored in the ops field of a
snd_soc_platform_driver structure or passed as the third argument to
snd_pcm_set_ops.  The corresponding field or parameter is declared const,
so snd_pcm_ops structures that have this property can be declared as const
as well.
These changes are in accordance with the upstream changes
in ASoC between Linux-4.4 and Linux-4.9 versions.

Change-Id: Ib772d7fc6df0b10b0bf134d1e1436f8cfced357a
Signed-off-by: Banajit Goswami <bgoswami@codeaurora.org>