drm/msm/sde: select the PM generic domain framework with DRM_MSM

Allow clients to vote for MDP power and clock resources through
SDE using the generic domain power management framework.  This
is used mainly by the v4l2 rotator driver.

Change-Id: Ieaa03e8e0944cf76caf979a2b86ca86859657b5a
Signed-off-by: Steve Cohen <cohens@codeaurora.org>