Change in coreboot[master]: Documentation/Intel: Add MultiProcessorInit documentation

[Subrata Banik (Code Review)]

Subrata Banik has posted comments on this change. ( https://review.coreboot.org/25921 )

Change subject: Documentation/Intel: Add MultiProcessorInit documentation
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Patch Set 3:
> (5 comments)
>
> Thanks for writing this up. The relation to the `SkipMpInit` wasn't
> clear to me before (I'm not 100% sure yet, but much closer).
>
> Please make it clear if you intend to force usage of this interface
> or if it is optional (for `SkipMpInit=1`).

Nothing is force here, its optional if you want to avoid FSP to use those interface which coreboot has published, then just set SkipMpInit=1, FSP won't call this APIs to run those feature programming over AP.