drm/i915: Eliminate the intel_dp dependency from DRRS

The DRRS code has no use for the intel_dp, replace it with
just a crtc pointer. This is just an intermediate step towards
making DRRS truly per-crtc.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220311172428.14685-12-ville.syrjala@linux.intel.com


Reviewed-by: Jani Nikula <jani.nikula@intel.com>