drm/msm/dsi: check return value for video done waits

Check for the return value of wait for video
done waits and print appropriate error message.

Signed-off-by: Abhinav Kumar <abhinavk@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>