msm: mdss: Add rotator sync point support in mdss

Currently rotation activities are blocking and hence hurt
the performance. So, make the calls asynchronous and use
sync point to realize this.

Change-Id: I677097fcaf133b0ed67ae94cfeacf3a0a10bc579
Signed-off-by: Jayant Shekhar <jshekhar@codeaurora.org>