Change in coreboot[master]: src/device/dram/ddr: Deduplicate enum spd_dimm_type_ddr{2,3,4}

[Angel Pons (Code Review)]

Attention is currently required from: Jakub Czapiga, Patrick Rudolph, Elyes Haouas.
Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/62181 )

Change subject: src/device/dram/ddr: Deduplicate enum spd_dimm_type_ddr{2,3,4}
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Patch Set 4: Code-Review+1

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/62181/comment/01d90110_0ff83748 
PS4, Line 9: While on it, fix SPD_DDR4_DIMM_TYPE_72B_SO_RDIMM and SPD_DDR4_DIMM_TYPE_72B_SO_UDIMM values
           : respectively to 0x08 and 0x09.
Please do this in a separate commit.