mb/google/nissa/var/sundance: Add WWAN power off sequence

Sundance support FM101 WWAN, use wwan_power.asl to handle the
power off sequence

BUG=b:343139385
TEST=Build and boot on sundance

Change-Id: I82085172db370ab5a6c0f77afe6042c53b89e43e
Signed-off-by: Leo Chou <leo.chou@lcfc.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/82683
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Eric Lai <ericllai@google.com>

src/mainboard/google/brya/Kconfig

@@ -413,6 +413,7 @@ config BOARD_GOOGLE_PUJJO
 config BOARD_GOOGLE_SUNDANCE
 	select BOARD_GOOGLE_BASEBOARD_NISSA
 	select DRIVERS_GENERIC_GPIO_KEYS
+	select HAVE_WWAN_POWER_SEQUENCE
 
 config BOARD_GOOGLE_PUJJOGA
 	select BOARD_GOOGLE_BASEBOARD_NISSA

src/mainboard/google/brya/variants/sundance/include/variant/gpio.h

@@ -5,4 +5,8 @@
 
 #include <baseboard/gpio.h>
 
+#define WWAN_FCPO	GPP_D6
+#define WWAN_RST	GPP_F12
+#define T2_OFF_MS	20
+
 #endif