Migrate mpq demux driver from kernel 4.4 to 4.9

This change migrates all the relevant files and updates made
to the dvb/demux framework, required for mpq demux driver.

The snapshot is taken as of msm-4.4,
'commit a74dd0fdc772 ("mmc: core: retune after un-gating the clocks")'
In addition, introduce a few code changes to reduce checkpatch
warnings, typos and other style issues.

Change-Id: Ifb50d730ff8bd245f5f96cd880dfe5c9a0a75fd2
Signed-off-by: Udaya Bhaskara Reddy Mallavarapu <udaym@codeaurora.org>