mb/google/rex: Set TCC to 90°C

Set tcc_offset value to 20 in devicetree for Thermal Control
Circuit (TCC) activation feature for rex variants.

BUG=b:270664854
BRANCH=None
TEST=Build FW and test on rex board

Change-Id: I0567b6240fcb53f38158c381b700169475cf3795
Signed-off-by: Sumeet Pawnikar <sumeet.r.pawnikar@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/76110
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>

src/mainboard/google/rex/variants/baseboard/rex/devicetree.cb

@@ -36,6 +36,9 @@ chip soc/intel/meteorlake
 	# DPTF enable
 	register "dptf_enable" = "1"
 
+	# Temporary setting TCC of 90C = Tj max (110) - TCC_Offset (20)
+	register "tcc_offset" = "20"
+
 	# Enable CNVi BT
 	register "cnvi_bt_core" = "true"