[XL] Change in coreboot[master]: soc/intel/xeon_sp: Rename nb_acpi.c and add SPR-SP support

[Jian-Ming Wang (Code Review)]

Attention is currently required from: Patrick Rudolph, Jonathan Zhang, Simon Chou, TimLiu-SMCI, Johnny Lin, Christian Walter, Angel Pons, Arthur Heymans, Tim Chu, Shelly Chang.

Jian-Ming Wang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/71958 )

Change subject: soc/intel/xeon_sp: Rename nb_acpi.c and add SPR-SP support
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Patch Set 8:

(1 comment)

File src/soc/intel/xeon_sp/uncore_acpi.c:

https://review.coreboot.org/c/coreboot/+/71958/comment/e5aac4d3_ed78fe6e 
PS2, Line 147: pds.
> pds is short for Proximity Domains. […]

The pds is a global variable defined in numa.h which is not included in this patch. Details could be find from the header.

I can't find specific rule for global variable from coding convention of coreboot. Possible we could use g_pds, G_pds, or even g_proximity_domains as improvement for readability. Since the improvement can impact multiple files across different changes and many code reviews are on going, suggest to do the improvement in near future.