msm: rotator: sync point support
Add MSM_ROTATOR_IOCTL_BUFFER_SYNC ioctl interface.
Rotator will create a timeline for each session at START, wait for
input fence and create released fence in this ioctl call,
signal the timeline after rotation is done.

Change-Id: I4682b0891e996111d97c345a97d5ce81ffb31c7d