Change in coreboot[master]: cpu/intel/car/p4: Add support x86_64

[Arthur Heymans (Code Review)]

Attention is currently required from: Angel Pons, Patrick Rudolph.
Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/56021 )

Change subject: cpu/intel/car/p4: Add support x86_64
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Patch Set 2:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/56021/comment/2e8d2b1c_c88b7fed 
PS1, Line 7: Add support x86_64
> Either `Add support for x86_64` or `Add x86_64 support`

Done

Patchset:

PS1:
> Will need to rebase atop what's merged of https://review.coreboot.org/q/topic:%22x86_64-kconfig%22

Done.