msm: sde: Enable traffic shaping for 4k@30fps rotation

For 30fps rotation, it is only required to perform a commit every other
vsync for a 60fps refresh rate panel. Rotation time for a 4k resolution
will take approx 12ms including SW overhead, and leave very little room
to perform a frame commit in fb driver. One way is to delay the
rotation time by enabling traffic shaping for 4k@30fps content so that
the it will take approx 15ms to finish, and that will force the frame
commit into next vsync time slot and thus matching the cadence of
30fps commit time.

CRs-Fixed: 1100633
Change-Id: I0aecfe767cd77140f75bb13c4fe6f9267d4d911e
Signed-off-by: Benjamin Chan <bkchan@codeaurora.org>