BACKPORT: drm/i915: Convert intel_crtc.c to struct intel_display

struct intel_display will replace struct drm_i915_private as
the main thing for display code. Convert intel_crtc.c code to
use it.

Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250206185533.32306-5-ville.syrjala@linux.intel.com


(cherry picked from commit b2479f72)

Conflicts:
   drivers/gpu/drm/i915/display/intel_crtc.h

Bug: 432032023
Test: None
Change-Id: I4b3ca73262651662e6816debe28c15de1354b0ac
Signed-off-by: Ap, Kamal <kamal.ap@intel.corp-partner.google.com>