mb/google/rex: Enable EC

Perform EC initialization in bootblock and ramstages. Add associated
ACPI configuration.

BUG=b:224325352
TEST=util/abuild/abuild -p none -t google/rex -a -c max

Signed-off-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Signed-off-by: Subrata Banik <subratabanik@google.com>
Change-Id: I2ea934f32b34bc43650e20dd2736f4e652004dc2
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64622
Reviewed-by: Tarun Tuli <taruntuli@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/mainboard/google/rex/Kconfig b/src/mainboard/google/rex/Kconfig
index d848ac7..dbccce6 100644
--- a/src/mainboard/google/rex/Kconfig
+++ b/src/mainboard/google/rex/Kconfig
@@ -7,6 +7,8 @@
 config BOARD_GOOGLE_BASEBOARD_REX
 	def_bool n
 	select BOARD_GOOGLE_REX_COMMON
+	select EC_GOOGLE_CHROMEEC
+	select EC_GOOGLE_CHROMEEC_ESPI
 	select SOC_INTEL_METEORLAKE
 	select SYSTEM_TYPE_LAPTOP
 
@@ -19,6 +21,10 @@
 	string
 	default "rex" if BOARD_GOOGLE_BASEBOARD_REX
 
+config CHROMEOS
+	select GBB_FLAG_DISABLE_EC_SOFTWARE_SYNC
+	select VBOOT_LID_SWITCH
+
 config DEVICETREE
 	default "variants/baseboard/\$(CONFIG_BASEBOARD_DIR)/devicetree.cb"