[M] Change in coreboot[master]: soc/intel: Use common codeflow for MP init

[Arthur Heymans (Code Review)]

Attention is currently required from: Nico Huber, Sean Rhodes, Tarun Tuli, Subrata Banik, Jonathan Zhang, Johnny Lin, Kapil Porwal, Christian Walter, Lean Sheng Tan, Werner Zeh, Tim Chu.

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/72604 )

Change subject: soc/intel: Use common codeflow for MP init
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Patch Set 3:

(1 comment)

File src/soc/intel/xeon_sp/cpx/cpu.c:

https://review.coreboot.org/c/coreboot/+/72604/comment/bf8de427_81e8d5e9 
PS2, Line 224: dev->link_list
> Looks like this was broken like APL? If so, please mention that in the
> commit message. :)

Done.