disp: msm: sde: update encoder atomic check during qsync usecase

During cwb usecases, connectors_changed flag will be
set and needs modeset condition will be set to true. This
change updates qsync concurrency check with modeset to
fail atomic check only if there is seamless poms, dms or
dynamic clock change scenario.

Change-Id: I78c214f9a6b08890b9b1618396becd3181c4a19b
Signed-off-by: Yashwanth <yvulapu@codeaurora.org>