drm/i915: Plumb crtc_state to PSR enable/disable

The PSR enable/disable need to know things about the crtc state, so
plumb it through. This will become even more important when we start
to reuse the generic infoframe code for the VSC DIP programming as the
infoframe code wants the crtc state as well.

v2: Fix kernel docs

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170818134958.15502-7-ville.syrjala@linux.intel.com