Change in coreboot[master]: [WIP] mainboards: Drop PWRS from GNVS

[Lance Zhao (Code Review)]

Attention is currently required from: Raul Rangel, Mariusz Szafrański, Angel Pons, Kyösti Mälkki, Andrey Petrov, Patrick Rudolph, Jason Glenesk, Damien Zammit, Marshall Dawson, Suresh Bellampalli, Vanessa Eusebio, Michal Motyl, Alexander Couzens, Felix Held.
Lance Zhao has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/49352 )

Change subject: [WIP] mainboards: Drop PWRS from GNVS
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Patch Set 8:

(1 comment)

Patchset:

PS8: 
I agree with this change about drop PWRS, that shall be done by platform but not soc. But again do we have better option other than dsdt_top.asl? That will make a system without anything to do with AC/DC power state will have an extra name?