Starting from xehpsdv, bit 0 of the GuC shim control register has
been repurposed, while bit 2 is now reserved, so we need to avoid
setting those for their old meaning on newer platforms.

Cc: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Cc: Stuart Summers <stuart.summers@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220120222436.3449778-1-daniele.ceraolospurio@intel.com