drm/i915/adl_s: Re-use TGL GuC/HuC firmware

ADL-S, like RKL, uses the same internal device ID for the GuC and HuC as
TGL did, making them all firmware-compatible.  Let's re-use TGL's
firmware for ADL-S.

Bspec: 50668
Cc: John Harrison <John.C.Harrison@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Aditya Swarup <aditya.swarup@intel.com>
Reviewed-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210129182945.217078-4-aditya.swarup@intel.com