[XL] Change in coreboot[main]: soc/intel/xeon_sp: Add Xeon ICX-SP support

[Shuo Liu (Code Review)]

Attention is currently required from: Christian Walter, Johnny Lin, Jonathan Zhang, Patrick Rudolph, Tim Chu.

Shuo Liu has posted comments on this change by Patrick Rudolph. ( https://review.coreboot.org/c/coreboot/+/85845?usp=email )

Change subject: soc/intel/xeon_sp: Add Xeon ICX-SP support
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Patch Set 3:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/85845/comment/169d5656_645287ba?usp... :
PS3, Line 9: Add support for the 1st Gen 10nm Xeon-SP CPUs. Supported and tested
ICX is 3rd gen

https://review.coreboot.org/c/coreboot/+/85845/comment/7e90eed9_49aa8d78?usp... :
PS3, Line 10: are dual socket systems with a LBG PCH.
So this is tested on a real ICX-SP hardware?