msm: mdss: release rotator sessions when all panels are suspended

When all panels are suspended MDP will be shutdown, need to ensure that
all rotator sessions are finished and properly closed to avoid access to
MDP hw.

CRs-Fixed: 409234
Change-Id: Ic1d95365a28c453ec8779d9c482a885857bf6912
Signed-off-by: Adrian Salido-Moreno <adrianm@codeaurora.org>