drm/msm: add additional HDR state transition

Add an additional HDR state transition to cover the HDR
teardown sequence case.

This will avoid the HDR infoframe to be programmed repeatedly
if there is no change in its contents.

Change-Id: Ic2f077f0c2ff01e19db5a59b218c4d824e039773
Signed-off-by: Abhinav Kumar <abhinavk@codeaurora.org>
Signed-off-by: Navid Bahrani <nbahrani@codeaurora.org>