[coreboot-gerrit] Change in coreboot[master]: arch/x86/smbios.c: Add SMBIOS type 17 for empty DIMM slots

[Angel Pons (Code Review)]

Attention is currently required from: Arthur Heymans, Patrick Rudolph, Paul Menzel, Jingle Hsu, Nill Ge, Marc Jones, Nico Huber, Subrata Banik, Johnny Lin, lichenchen.carl, Tim Chu, Shelly Chang.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/63882 )

Change subject: arch/x86/smbios.c: Add SMBIOS type 17 for empty DIMM slots
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Patch Set 8:

(1 comment)

Patchset:

PS8:
> But there's no need to create any meminfo entries with `dimm_present` set to `IGNORED_DIMM`. […]

I made CB:64035 and CB:64036 which should provide the needed functionality for xeon_sp/cpx. The only thing to do is define the `mainboard_dimm_slot_exists()` function in mainboard code so that it returns true for existing DIMM slots, based on socket/channel/dimm/slot number.