msm: mdss: Allow display commit in DCM state for CMD panels

Allow display-commit in DCM state for command mode panels. QDCM
tool requires explicit display kickoff during the calibration
stage in which the panel power is turned off.

Change-Id: Id6c7a0becf488ad2bfe9652b05d781384109f5c4
Signed-off-by: Zohaib Alam <zalam@codeaurora.org>