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

The PP compat layer now has CSC functionality. There are compat copy
functions for each of the CSC related PP structures, in order to
simplify the adding of new fields to the structures in the future.

Signed-off-by: Benet Clark <benetc@codeaurora.org>
Change-Id: Icdae479a655d8d8cf5cce66682b611edd587ba06