[S] Change in coreboot[master]: soc/amd/common/block/cpu: Add missing cbfs_unmap()

[Arthur Heymans (Code Review)]

Attention is currently required from: Konrad Adamczyk, Jason Glenesk, Raul Rangel, Jakub Czapiga, Matt DeVillier, Paul Menzel, Grzegorz Bernacki, Tim Van Patten, Fred Reitberger, Karthik Ramasubramanian, Felix Held.

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74777 )

Change subject: soc/amd/common/block/cpu: Add missing cbfs_unmap()
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Patch Set 1: Code-Review-1

(1 comment)

File src/soc/amd/common/block/cpu/update_microcode.c:

https://review.coreboot.org/c/coreboot/+/74777/comment/109ea493_6db27134 
PS1, Line 110: 	c
Updating microcode happens in parallel if I recall correctly. You need to use an atomic operation (atomic_t).