disp: msm: avoid vsync delay during seamless mode switch

Remove sde rscc vsync wait requirement during seamless
mode switch state transition to reduce the transition
delay. SDE RSCC rev 3.0 only keeps vsync wait requirement
for solver mode disable.

Change-Id: I6119dbb97d47a70eecc9e5d356c648003adfcc29
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>