As for display, the intent is to share the display code with the i915
driver so that there is maximum reuse there.

We do this by recompiling i915/display code twice.
Now that i915 has been adapted to support the Xe build, we can add
the xe/display support.

This initial work is a collaboration of many people and unfortunately
this squashed patch won't fully honor the proper credits.
But let's try to add a few from the squashed patches:
Co-developed-by: Matthew Brost <matthew.brost@intel.com>
Co-developed-by: Jani Nikula <jani.nikula@intel.com>
Co-developed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Co-developed-by: Matt Roper <matthew.d.roper@intel.com>
Co-developed-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Co-developed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Co-developed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>