drm/msm/sde: Add REG DMA support for SSPP features

On SDM855, a couple of LUT based features are introduced to SSPP.
This change adds the support for these features using REG DMA.

Change-Id: Id117d9ab626c5fe427358fe07810cb58329e75ed
Signed-off-by: Ping Li <pingli@codeaurora.org>