msm: mdss: Add ARGC compat ioctl to PP compat layer

Added ARGC to the PP LUT compat framework. There are compat copy functions
for each of the ARGC related PP structures, in order to simplify the
addition of new fields to the structures in the future.

Signed-off-by: Benet Clark <benetc@codeaurora.org>
Change-Id: I74ebaeef8402f8de6f67a3f906f8100b6a56de21