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

[Rasheed Hsueh (Code Review)]

Attention is currently required from: Derek Huang, Kapil Porwal, Nick Vaccaro, Paul Menzel.

Rasheed Hsueh 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 5:

(1 comment)

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

https://review.coreboot.org/c/coreboot/+/80342/comment/52904965_cc379899 :
PS5, Line 3:         device domain 0 on
           :         end
> Should tabs be used for indentation?

It was created auto-script, how about letting us change our coreboot CL and fixed in the next patch?