mdss: display: Fix DCS command parsing for short commands
mdss: display: Fix DCS command parsing for short commands

The DCS short command might have zero payload. Fix the
command size check for zero payload.

Change-Id: Idb5220c90bd7ee52bfa2e049861dda131785bbee
CRs-Fixed: 547774
Signed-off-by: Chandan Uddaraju <fab05c666e65bf0dd1fee237b8e4ae910601e323@codeaurora.org>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas