Change in coreboot[master]: cezanne/psp_verstage: populate a/b firmware

[Arthur Heymans (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Marshall Dawson, Kangheui Won, Felix Held.
Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/52961 )

Change subject: cezanne/psp_verstage: populate a/b firmware
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Patch Set 1:

(1 comment)

File src/mainboard/google/guybrush/Kconfig:

https://review.coreboot.org/c/coreboot/+/52961/comment/dce2ce76_d37a0a91 
PS1, Line 74: config CEZANNE_FW_A_POSITION
            : 	hex
            : 	default 0xFF012040
            : 	depends on VBOOT_SLOTS_RW_AB
            : 	help
            : 	  Location of the AMD firmware in the RW_A region. This is the
            : 	  start of the RW-A region + 64 bytes for the cbfs header.
            : 
            : config CEZANNE_FW_B_POSITION
            : 	hex
            : 	default 0xFF312040
            : 	depends on VBOOT_SLOTS_RW_AB
            : 	help
            : 	  Location of the AMD firmware in the RW_B region. This is the
            : 	  start of the RW-A region + 64 bytes for the cbfs header.
Please parse $(obj)/fmap_config.h to figure this out instead of hardcoding it in Kconfig which has to be manually maintained to match the fmap.