Change in coreboot[master]: soc/amd/cezanne: Add verstage support

[Martin Roth (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Marshall Dawson, Felix Held.
Martin Roth has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/50342 )

Change subject: soc/amd/cezanne: Add verstage support
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Patch Set 2:

(1 comment)

File src/soc/amd/cezanne/Kconfig:

https://review.coreboot.org/c/coreboot/+/50342/comment/b68fa45e_92733190 
PS2, Line 128: config VBOOT
             : 	select VBOOT_STARTS_IN_BOOTBLOCK
             : 	select VBOOT_SEPARATE_VERSTAGE
> Wasn't suggesting anything 😊  Only trying to sanity-check.  I'm fine with it.

I think it should go in the mainboard.  We plan on supporting both PSP and x86 verstages again, correct?