mb/google/brya/var/kano: Enable SaGv support

Enable SaGv support for kano

BUG=None
TEST=FW_NAME=kano emerge-brya coreboot

Signed-off-by: David Wu <david_wu@quanta.corp-partner.google.com>
Change-Id: Ifc537a5137f5e6eb10cd4c160923ea4da1f6b0d0
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57876
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

src/mainboard/google/brya/variants/kano/overridetree.cb

@@ -9,6 +9,8 @@ fw_config
 	end
 end
 chip soc/intel/alderlake
+	register "SaGv" = "SaGv_Enabled"
+
 	# Intel Common SoC Config
 	#+-------------------+---------------------------+
 	#| Field             |  Value                    |