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

[Grzegorz Bernacki (Code Review)]

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

Grzegorz Bernacki has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74779 )

Change subject: soc/amd/common/block/graphics: Add missing cbfs_unmap()
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Patch Set 2:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/74779/comment/46499acc_28df9e12 
PS1, Line 9: cbfs_map() can allocate memory, so cbfs_unmap() should be
           : called before leaving the function.
> This needs to be updated, since `cbfs_unmap()` isn't being called here anymore.

Done