mb/google/dedede/var/magolor: Support VBT for Magister

Default VBT supports only integrated Display port. Magister supports a
HDMI port and hence support a separate VBT for Magister.

BUG=b:180666608
BRANCH=dedede
TEST=Build and boot to OS.

Cq-Depend: chrome-internal:3661227
Signed-off-by: David Wu <david_wu@quanta.corp-partner.google.com>
Change-Id: I52c10452887312959f68cfc4e25d5897dae388f8
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51279
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

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

@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 
+#include <drivers/intel/gma/opregion.h>
 #include <fw_config.h>
 #include <sar.h>
 
@@ -10,3 +11,11 @@ const char *get_wifi_sar_cbfs_filename(void)
 
 	return WIFI_SAR_CBFS_DEFAULT_FILENAME;
 }
+
+const char *mainboard_vbt_filename(void)
+{
+	if (fw_config_probe(FW_CONFIG(DB_PORTS, DB_PORTS_1A_HDMI)))
+		return "vbt_magister.bin";
+
+	return "vbt.bin";
+}