mb/novacustom/mtl-h/var/igpu: Add power limits

Set PL4 to the wattage of the included AC adapter. The EC will override
this limit at runtime, if necessary (for example, if a weaker USB-PD
power supply is connected).

PsysPmax is set according to the board schematics (RPsys resistor),
which ensures that the Psys signal generated by the battery charger and
interpreted by SOC VRs is interpreted correctly and that Psys power
limits applied by the EC work as expected.

Change-Id: I56e9c20556553940c308150f7e470628f56c3991
Signed-off-by: Michał Kopeć <michal.kopec@3mdeb.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/86752
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michał Żygowski <michal.zygowski@3mdeb.com>

src/mainboard/novacustom/mtl-h/variants/igpu/overridetree.cb

@@ -1,4 +1,16 @@
 chip soc/intel/meteorlake
+	# Power limits,
+	# PsysPL2, PsysPL3, PL4 are configured by EC at runtime
+	register "power_limits_config[MTL_P_682_482_CORE]" = "{
+		.tdp_pl1_override = 35,
+		.tdp_pl2_override = 64,
+		.tdp_pl4 = 90,
+		.psys_pmax = 99,
+	}"
+
+	# MTL SOC has additional setting for PsysPmax
+	register "psys_pmax_watts" = "99"
+
 	device domain 0 on
 		subsystemid 0x1558 0xa743 inherit
 		device ref igpu on