[S] Change in coreboot[main]: mb/google/brya: Create yavista variant

[Henry Sun (Code Review)]

Attention is currently required from: Derek Huang, Dinesh Gehlot, Eric Lai, Garen Wu, Kapil Porwal, Nick Vaccaro, Rasheed Hsueh.

Henry Sun has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/80342?usp=email )

Change subject: mb/google/brya: Create yavista variant
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Patch Set 6:

(1 comment)

Patchset:

PS6: 
Hi Garen/Rash,

Missing the V+1 vote here. please update local test and vote if it's done. Thanks!