msm_fb: Wifi display changes for commit ioctl

This change handles panel updates for WFD panel via
overlay_commit interface, along with conglomeration of
some common code across pan_update and overlay_commit ioctls

Signed-off-by: Kalyan Thota <kalyant@codeaurora.org>

Conflicts:

	drivers/video/msm/mdp4_overlay.c
	drivers/video/msm/msm_fb.c
	include/linux/msm_mdp.h

Change-Id: I9e332856782c59ab598bb388a2ec482076746ad2
Signed-off-by: Sudhir Sharma <sudsha@codeaurora.org>