[M] Change in coreboot[main]: soc/intel/common: Add support for RTD3 on CNVi

[Matt DeVillier (Code Review)]

Attention is currently required from: Cliff Huang, Intel coreboot Reviewers, Jérémy Compostella, Nick Vaccaro, Sean Rhodes.

Matt DeVillier has posted comments on this change by Sean Rhodes. ( https://review.coreboot.org/c/coreboot/+/86403?usp=email )

Change subject: soc/intel/common: Add support for RTD3 on CNVi
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Patch Set 21:

(1 comment)

Patchset:

PS20:
> should we check if Chipset has support for RTD3 or not ?

might not be necessary, since everything is conditional (CondRefOf) on the control method, and that being present depends on the GPIO being defined in devicetree, so it's a no-op for all boards ATM