msm: display: add sync point support in overlay commit

Wait for fence signaled before commit, signal previous
fence after commit done. Same as pan display

(cherry picked from commit e622fc13cb58becfc077a830421e471abcc08140)

Change-Id: Ic7f95de86c5776a17ab1e5b7457e2dfb1108b576
Signed-off-by: Ken Zhang <kenz@codeaurora.org>
Signed-off-by: Siddhartha Agrawal <agrawals@codeaurora.org>

Conflicts:

	drivers/video/msm/msm_fb.c