drm/msm/sde: enable async inline rotation

Switch inline rotation to use asynchronous mode for command
mode panels so that the rotator can start before the previous
frame has been completed. This helps to prevent dropped frames
during high fps use cases.

Change-Id: Iaed07b88fb5549c07bdf7a9dd2baa57c9b3016d9
Signed-off-by: Clarence Ip <cip@codeaurora.org>