[M] Change in coreboot[master]: mb/google/rex: Add DTT thermal settings for policies

[Sumeet R Pawnikar (Code Review)]

Attention is currently required from: Tarun Tuli, Subrata Banik, Ravishankar Sarawadi, Kapil Porwal, John Zhao, Ivy Jian, Eric Lai, Peter Ou.

Sumeet R Pawnikar has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/71166 )

Change subject: mb/google/rex: Add DTT thermal settings for policies
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Patch Set 6:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/71166/comment/db6dc31c_59d1c8a6 
PS5, Line 13: =Built and tested on Rex board
> wondering if u can add more specific test details to support this work?

Done

File src/mainboard/google/rex/variants/rex0/overridetree.cb:

https://review.coreboot.org/c/coreboot/+/71166/comment/258222ee_dae41a4e 
PS5, Line 129: # TODO: below values are initial reference values only
> can u please keep a bug open for tracking purpose and add here as `FIXME`?

Yes, I'll keep this b:270664854 for tracking purpose. Updated FIXME tag here.