drm/msm/sde: program dither based on input data

This change programs dither based on user mode input data and
reprograms the dither when device comes out of power collapse.

Change-Id: I83be20c8eb2dc2221cc57cd2395f6512338ff6ef
Signed-off-by: Narendra Muppalla <NarendraM@codeaurora.org>
Signed-off-by: Nirmal Abraham <nabrah@codeaurora.org>