[M] Change in coreboot[master]: mb/google/skyrim/var/winterhold: update thermal config

[Dtrain Hsu (Code Review)]

Attention is currently required from: Jason Nien, EricKY Cheng, Chris Wang, Martin Roth, Eric Peers, Karthikeyan Ramasubramanian.

Dtrain Hsu has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/68472 )

Change subject: mb/google/skyrim/var/winterhold: update thermal config
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Patch Set 31: Code-Review+1

(1 comment)

File src/mainboard/google/skyrim/variants/winterhold/overridetree.cb:

https://review.coreboot.org/c/coreboot/+/68472/comment/360f7778_ded67faf 
PS31, Line 7: # Refer the spec "FT6 Infrastructure Roadmap"#57316
            : 	# Set system_configuration to 4 for 15W
            : 	register "system_configuration" = "4"
Base on CB:69904, I found below are the same with baseboard settings. Will you remove it later or on this CL?
```
system_configuration
fast_ppt_limit_mW
sustained_power_limit_mW
vrm_current_limit_mA
vrm_maximum_current_limit_mA
vrm_soc_current_limit_mA
vrm_current_limit_throttle_mA
vrm_maximum_current_limit_throttle_mA
```