drm/msm/sde: add support for histogram properties

PA histogram feature is needed for ABA features in display
postprocessing. Change adds histogram control property to
enable and disable histogram feature. Add histogram interrupt
property to enable histogram interrupt notification. Add
histogram operation support to control histogram feature and
read histogram data for version 1.7.

Change-Id: Ifee38b42e4322f703406fe2468d960e6b174fffc
Signed-off-by: Xu Yang <yangxu@codeaurora.org>