drm/msm/sde: update rotate flush determination

Set the rotate flush bit in the hardware if an inline
rotation was committed or the inline/offline status is
changing, rather than determining it from the current
and past plane rotate statuses. This allows the driver
to properly handle commits that don't update the rotated
planes while inline rotation is active.

Change-Id: Ia1dfd45d7a1a5d164ba3b5d7202bc7dd4b953781
Signed-off-by: Clarence Ip <cip@codeaurora.org>