[S] Change in coreboot[master]: mb/google/rex: Add devtree update support for variants

[Sumeet R Pawnikar (Code Review)]

Attention is currently required from: Tarun Tuli, Subrata Banik, Kapil Porwal, Eric Lai.

Sumeet R Pawnikar has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74379 )

Change subject: mb/google/rex: Add devtree update support for variants
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Patch Set 4:

(2 comments)

File src/mainboard/google/rex/mainboard.c:

https://review.coreboot.org/c/coreboot/+/74379/comment/51b95e0c_67ad3e8f 
PS2, Line 36: variant_devtree_update
> Based on above comment, moving required things under baseboard rex to avoid repeat of code.

Done

File src/mainboard/google/rex/variants/rex0/ramstage.c:

https://review.coreboot.org/c/coreboot/+/74379/comment/521b03a6_211800ed 
PS2, Line 17: }
> > I feel this above way of filling information is only applicable if we are sure that rex0 board won […]

Done