mb/google/dedede/var/magolor: Add Wifi SAR for magolor and maglia

Add wifi sar for magolor and maglia:
Using tablet mode of fw config to decide to load custom wifi sar or not.
same wifi sar value for magolor and maglia (shared firmware)

BUG=b:173001370, b:173001251
TEST=enable CHROMEOS_WIFI_SAR in config of coreboot,
emerge-dedede coreboot-private-files-baseboard-dedede coreboot chromeos-bootimage.

Cq-Depend: chrome-internal:3453724

Signed-off-by: Ren Kuo <ren.kuo@quanta.corp-partner.google.com>
Change-Id: I44ab68c9ee5deced90d3858161571ab4b39b4c8a
Reviewed-on: https://review.coreboot.org/c/coreboot/+/48448
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/mainboard/google/dedede/Kconfig.name

@@ -66,6 +66,7 @@ config BOARD_GOOGLE_MAGOLOR
 	select BOARD_GOOGLE_BASEBOARD_DEDEDE
 	select BASEBOARD_DEDEDE_LAPTOP
 	select DRIVERS_INTEL_MIPI_CAMERA
+	select GEO_SAR_ENABLE if CHROMEOS_WIFI_SAR
 	select SOC_INTEL_COMMON_BLOCK_IPU
 
 config BOARD_GOOGLE_METAKNIGHT

src/mainboard/google/dedede/variants/magolor/Makefile.inc

@@ -0,0 +1,3 @@
+## SPDX-License-Identifier: GPL-2.0-or-later
+
+ramstage-$(CONFIG_FW_CONFIG) += variant.c

src/mainboard/google/dedede/variants/magolor/variant.c

@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <fw_config.h>
+#include <sar.h>
+
+const char *get_wifi_sar_cbfs_filename(void)
+{
+	const char *filename = NULL;
+
+	if (fw_config_probe(FW_CONFIG(TABLETMODE, TABLETMODE_ENABLED)))
+		filename = "wifi_sar-magolor.hex";
+
+	return filename;
+}