mb/google/dedede/var/bugzzy: Add LTE power off sequence

This change adds LTE power off sequence for bugzzy.

BUG=None
BRANCH=dedede
TEST=FW_NAME=bugzzy emerge-dedede coreboot

Signed-off-by: Seunghwan Kim <sh_.kim@samsung.corp-partner.google.com>
Change-Id: I6be0e23b9c2c2bed9745011920394006fdaabae6
Reviewed-on: https://review.coreboot.org/c/coreboot/+/58443
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Henry Sun <henrysun@google.com>
Reviewed-by: Karthik Ramasubramanian <kramasub@google.com>

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

@@ -1,3 +1,5 @@
 ## SPDX-License-Identifier: GPL-2.0-or-later
 
 ramstage-y += gpio.c
+
+smm-y += variant.c

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

@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <acpi/acpi.h>
+#include <baseboard/variants.h>
+#include <delay.h>
+#include <gpio.h>
+
+static void power_off_lte_module(void)
+{
+	gpio_output(GPP_H17, 0);
+	mdelay(20);
+	gpio_output(GPP_A10, 0);
+}
+
+void variant_smi_sleep(u8 slp_typ)
+{
+	/*
+	 * Once the FW_CONFIG is provisioned, power off LTE module only under
+	 * the situation where it is stuffed.
+	 */
+	if (slp_typ == ACPI_S5)
+		power_off_lte_module();
+}