drm/i915/dsb: Convert the DSB code to use intel_display rather than i915

The future direction will be to mainly use intel_display
rather than i915 in the display code. Start on that path
for the DSB code.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240611133344.30673-8-ville.syrjala@linux.intel.com


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