mb/intel/adlrvp: Configure the external V1p05/Vnn/VnnSx rails

This patch configures external V1p05/Vnn/VnnSx rails for adlrvp-n
to achieve the better power savings.
* Enable the external V1p05, Vnn, VnnSx rails in S0i1, S0i2, S0i3, S3,
  S4, S5 , S0 states.
* Set the supported voltage states.
* Set the voltage for v1p05 and vnn.
* Set the ICC max for v1p05 and vnn.
Kit: 646929 - ADL N Platform Design Guide

BUG=b:223102016
TEST=Verified all the UPD values are updated with these configs.

Signed-off-by: V Sowmya <v.sowmya@intel.com>
Change-Id: I06298eb1aec07eae34420c5736e912c707fefbc4
Reviewed-on: https://review.coreboot.org/c/coreboot/+/63356
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Usha P <usha.p@intel.com>
Reviewed-by: Maulik V Vaghela <maulik.v.vaghela@intel.com>
Reviewed-by: Sumeet R Pawnikar <sumeet.r.pawnikar@intel.com>
Reviewed-by: Kangheui Won <khwon@chromium.org>
diff --git a/src/mainboard/intel/adlrvp/devicetree_n.cb b/src/mainboard/intel/adlrvp/devicetree_n.cb
index 40dba8b..4fc655c 100644
--- a/src/mainboard/intel/adlrvp/devicetree_n.cb
+++ b/src/mainboard/intel/adlrvp/devicetree_n.cb
@@ -136,6 +136,21 @@
 		},
 	}"
 
+	# Configure external V1P05/Vnn/VnnSx Rails
+	register "ext_fivr_settings" = "{
+		.configure_ext_fivr = 1,
+		.v1p05_enable_bitmap = FIVR_ENABLE_ALL_SX,
+		.vnn_enable_bitmap = FIVR_ENABLE_ALL_SX,
+		.vnn_sx_enable_bitmap = FIVR_ENABLE_ALL_SX,
+		.v1p05_supported_voltage_bitmap = FIVR_VOLTAGE_NORMAL,
+		.vnn_supported_voltage_bitmap = FIVR_VOLTAGE_MIN_ACTIVE,
+		.v1p05_voltage_mv = 1050,
+		.vnn_voltage_mv = 780,
+		.vnn_sx_voltage_mv = 1050,
+		.v1p05_icc_max_ma = 500,
+		.vnn_icc_max_ma = 500,
+	}"
+
 	device domain 0 on
 		device ref igpu on end
 		device ref ipu on