drm/msm/mdp5: Refactor mdp5_plane_atomic_check

In mdp5_plane_atomic_check, we get crtc_state from drm_plane_state.

Later, for cursor planes, we'll populate the update_plane() func that
takes a fast asynchronous path to implement cursor movements. There, we
would need to call a similar atomic_check func to validate the plane
state, but crtc_state would need to be derived differently.

Refactor mdp5_plane_atomic_check to mdp5_plane_atomic_check_with_state
such that the latter takes crtc_state as an argument.

This is similar to what the intel driver has done for async cursor
updates.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>