Change in coreboot[master]: mb/asus/p8x7x: Use native ram init and depricate mrc.bin code

[Angel Pons (Code Review)]

Attention is currently required from: Bill XIE.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/54336 )

Change subject: mb/asus/p8x7x: Use native ram init and depricate mrc.bin code
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Patch Set 3:

(1 comment)

Patchset:

PS3:
> Some things MRC does are missing from the native codepath, such as xHCI setup. […]

I made this patch series: https://review.coreboot.org/q/topic:%22unify-asus-p8z77-boards%22+status:ope...

I'd *much* prefer my approach over this. The commits in this patch train are either reproducible (coreboot.rom is identical before and after) or very small and easy to review. And I didn't need to drop MRC.bin support from P8Z77-M PRO either.