drm/i915/dg2: Add support for new DG2-G11 revid 0x5

The bspec has been updated with a new revision 0x5 that translates to B1
GT stepping and C0 display stepping.

Bspec: 44477
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210805163647.801064-2-matthew.d.roper@intel.com