[S] Change in coreboot[master]: soc/intel/xeon_sp: Improve FSP-S boottime for xeon-sp platform

[Paul Menzel (Code Review)]

Attention is currently required from: Patrick Rudolph, Johnny Lin, Christian Walter, Arthur Heymans, Shuming Chu (Shuming).

Paul Menzel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/71085 )

Change subject: soc/intel/xeon_sp: Improve FSP-S boottime for xeon-sp platform
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Patch Set 4: Code-Review+1

(3 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/71085/comment/70799696_e5e29d5f 
PS4, Line 7: soc/intel/xeon_sp: Improve FSP-S boottime for xeon-sp platform
Maybe:
> soc/intel/xeon_sp: Cache DRAM with TSEG for FSP-S boot time

https://review.coreboot.org/c/coreboot/+/71085/comment/5684fc6d_a11f7863 
PS4, Line 12: 
Maybe paste the MTRR before and after for easy comparison?

https://review.coreboot.org/c/coreboot/+/71085/comment/eb9799c5_ca2b60f6 
PS4, Line 13: TESTED on Archer City 2S: Boottime goes from ~19m to ~4m.
Minutes or seconds? ;-)