video: msm: Maintain histogram LUT state through suspend resume

Make sure LUT state is maintained after suspend resume. Required to ensure
HistLUT and backlight scale are in sync.

CRs-Fixed: 476491
Change-Id: Icc999aa0b04cad93ceed334426f61b71cbdd0a13
Signed-off-by: Carl Vanderlip <carlv@codeaurora.org>
Signed-off-by: Jeevan Shriram <jshriram@codeaurora.org>