Change in coreboot[master]: mb/google/nissa: Configure the external V1p05/Vnn/VnnSx rails for Niv...

[V Sowmya (Code Review)]

Attention is currently required from: Kangheui Won, Tim Wawrzynczak, Reka Norman, Vidya Gopalakrishnan, Vinay Kumar, Eric Lai, Baieswara Reddy Sagili.
V Sowmya has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63355 )

Change subject: mb/google/nissa: Configure the external V1p05/Vnn/VnnSx rails for Nivviks
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Patch Set 7:

(1 comment)

File src/mainboard/google/brya/variants/nivviks/overridetree.cb:

https://review.coreboot.org/c/coreboot/+/63355/comment/b4c309b7_73ac41bd 
PS6, Line 26: 	# FIVR configurations
> Changes should also apply to all ADL-N variants, so better to have it in mb/google/brya/baseboard/ni […]

We are currently not configuring these from the baseboard since we are not sure all the upcoming nissa variants will use the external bypass rails hence we are using the variant overrides.