msm_fb: display: add satge commit without pipes queued

This patch allow satge commit without pipes queued to
allow a pipe to be un-staged from mixer immediately after
overlay_unset.

Change-Id: I03abb907c66cce3d0559743d3bb1eb26a88dc78a
Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
Signed-off-by: Siddhartha Agrawal <agrawals@codeaurora.org>