Change in coreboot[master]: src/*: Specify type of `DIMM_SPD_SIZE` once

[Felix Held (Code Review)]

Attention is currently required from:  Felix Singer, Frans Hendriks, Jonathan Zhang, Angel Pons, Michael Niewöhner, Patrick Rudolph, Piotr Król, Anjaneya "Reddy" Chagam, Nico Huber, Michał Żygowski, Marshall Dawson, Johnny Lin, Tim Wawrzynczak, Morgan Jang, Wim Vervoorn.
Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/57257 )

Change subject: src/*: Specify type of `DIMM_SPD_SIZE` once
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Patch Set 1: Code-Review+1

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/57257/comment/444890d4_4a3aaf9c 
PS1, Line 9: Specify the type of the `DIMM_SPD_SIZE` Kconfig symbol once.
maybe add in which Kconfig file the type is defined?