[L] Change in coreboot[main]: soc/xeon_sp: Initially add N-1 IBL codes

[Patrick Rudolph (Code Review)]

Attention is currently required from: Arthur Heymans, Christian Walter, David Hendricks, Johnny Lin, Jonathan Zhang, Lean Sheng Tan, Shuo Liu, TangYiwei, Tim Chu.

Patrick Rudolph has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/81315?usp=email )

Change subject: soc/xeon_sp: Initially add N-1 IBL codes
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Patch Set 11: Code-Review-2

(1 comment)

Patchset:

PS11: 
There's no need to add tons of code that won't ever be used since the HW for it just doesn't exist on IBL.
When you want to have something that builds simply use the existing EBG PCH code.