drm/i915/mtl: Add Wa_22015279794

Wa_22015279794 applies to MTL P from stepping A0 to B0 (exclusive).

Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230329212336.106161-3-gustavo.sousa@intel.com