drm/xe/xe2: AuxCCS is no longer used

Starting with Xe2, all platforms (including igpu platforms) use FlatCCS
compression rather than AuxCCS.  Similar to PVC, any future platforms
that don't support FlatCCS should not attempt to fall back to AuxCCS
programming.

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>