drm/i915/display: split out crtc state dump to a separate file

Declutter intel_display.c by splitting out crtc state dumping to a
separate file.

v2: intel_pipe_config_dump -> intel_crtc_state_dump

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/f72a5626473692910263671af91e02251ed87eea.1655372759.git.jani.nikula@intel.com