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

[Kyösti Mälkki (Code Review)]

Attention is currently required from: Raul Rangel, Mariusz Szafrański, Angel Pons, Andrey Petrov, Patrick Rudolph, Lance Zhao, Jason Glenesk, Damien Zammit, Marshall Dawson, Suresh Bellampalli, Vanessa Eusebio, Michal Motyl, Alexander Couzens, Felix Held.
Kyösti Mälkki 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:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/49352/comment/a6164d85_8cfe1441 
PS8, Line 11: whether plugged on the charger or not.
> Does any SMI handler need to access PWRS?

Currently no; in the future who knows.

Patchset:

PS8:
> We already had this extra name in GNVS

One can improve from this if really necessary; declare it Extern (PWRS) and have Name (PWRS) appear under ec/. But therw are some \PWRS references under soc/amd and soc/intel/baytrail that need a solution for non-EC platforms then.