[S] Change in coreboot[master]: soc/amd/mendocino: Update build rules for PSP BIOS image

[Raul Rangel (Code Review)]

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

Raul Rangel has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/68136 )

Change subject: soc/amd/mendocino: Update build rules for PSP BIOS image
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Patch Set 9:

(2 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/68136/comment/8217de14_bfd4b95e 
PS9, Line 9: Donot
Do not

https://review.coreboot.org/c/coreboot/+/68136/comment/045fe1ab_722d7205 
PS9, Line 9: enabled
Can you add the reason why we don't compress. I'm assuming it's so we can easily skip the signing verification of the metadata hash.