{commonlib, libpayload}: Add RTC_WAKE to boot_mode_t

Define CB_BOOT_MODE_RTC_WAKE and LB_BOOT_MODE_RTC_WAKE in the
coreboot table headers. This allows the firmware to communicate
to the payload (such as depthcharge) that the device started
up due to a Real-Time Clock alarm.

Synchronize the change across:
- payloads/libpayload/include/coreboot_tables.h
- src/commonlib/include/commonlib/coreboot_tables.h

BUG=b:493760057
BRANCH=none
TEST=Build coreboot and libpayload. Verify that the new boot mode
is accessible in the payload.

Change-Id: I8f5e118e6965f29498ab5bb46e153bc6d24bc116
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/91764
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

payloads/libpayload/include/coreboot_tables.h

@@ -464,6 +464,8 @@ enum boot_mode_t {
 	CB_BOOT_MODE_LOW_BATTERY_CHARGING,
 	/* Device is booting in due to charger insertion */
 	CB_BOOT_MODE_OFFMODE_CHARGING,
+	/* Device is booting in due to RTC alarm */
+	CB_BOOT_MODE_RTC_WAKE,
 };
 
 /*

src/commonlib/include/commonlib/coreboot_tables.h

@@ -647,6 +647,8 @@ enum boot_mode_t {
 	LB_BOOT_MODE_LOW_BATTERY_CHARGING,
 	/* Device is booting in due to charger insertion */
 	LB_BOOT_MODE_OFFMODE_CHARGING,
+	/* Device is booting in due to RTC alarm */
+	LB_BOOT_MODE_RTC_WAKE,
 };
 
 /*