mb/google/rex/var/kanix: Add WIFI SAR table

Add WIFI SAR table for kanix.

BUG=b:399484050
BRANCH=firmware-rex-15709.B
TEST=emerge-rex coreboot chromeos-bootimage

Change-Id: Ie4c549ea507b2f823ce54a0e4476f4f82a037865
Signed-off-by: Kenneth Chan <kenneth.chan@quanta.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/86931
Reviewed-by: Subrata Banik <subratabanik@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/rex/variants/kanix/Makefile.mk

@@ -5,3 +5,4 @@ romstage-y += gpio.c
 ramstage-$(CONFIG_FW_CONFIG) += fw_config.c
 ramstage-y += gpio.c
 ramstage-y += ramstage.c
+ramstage-y += variant.c

src/mainboard/google/rex/variants/kanix/variant.c

@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <baseboard/variants.h>
+#include <chip.h>
+#include <fw_config.h>
+#include <sar.h>
+
+const char *get_wifi_sar_cbfs_filename(void)
+{
+	return get_wifi_sar_fw_config_filename(FW_CONFIG_FIELD(WIFI_TYPE));
+}
+
+void variant_update_soc_chip_config(struct soc_intel_meteorlake_config *config)
+{
+	config->cnvi_bt_audio_offload = true;
+}