[M] Change in coreboot[master]: soc/amd/common/block/apob: Add hashed APOB support

[Raul Rangel (Code Review)]

Attention is currently required from: Jason Glenesk, Matt DeVillier, Martin Roth, Fred Reitberger, Felix Held.

Raul Rangel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/67301 )

Change subject: soc/amd/common/block/apob: Add hashed APOB support
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Patch Set 2: Code-Review+1

(3 comments)

File src/soc/amd/common/block/apob/apob_cache.c:

https://review.coreboot.org/c/coreboot/+/67301/comment/bd3a6441_2302ed84 
PS2, Line 22: RW_MRC_HASH
Curious if we can just place the hash at the end of the APCB so we can reuse the `RW_MRC_CACHE`? Or do we not have enough space?

https://review.coreboot.org/c/coreboot/+/67301/comment/0efe88e8_8d3455f1 
PS2, Line 162: sizeof(hash)
I would add an assert somewhere that verifies `sizeof(has) <= DEFAULT_MRC_HASH_SIZE`

https://review.coreboot.org/c/coreboot/+/67301/comment/fae00537_cf01339e 
PS2, Line 233: memcmp
Add a `!update_needed && `. No reason to read the APOB if we already determined if it needs to be updated.