Change in coreboot[master]: amdfwtool: Add support for A/B recovery

[Bao Zheng (Code Review)]

Attention is currently required from: Jason Glenesk, Raul Rangel, Martin Roth, Marshall Dawson, Zheng Bao, Felix Held.
Bao Zheng has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/56773 )

Change subject: amdfwtool: Add support for A/B recovery
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Patch Set 9:

(1 comment)

File util/amdfwtool/amdfwtool.c:

https://review.coreboot.org/c/coreboot/+/56773/comment/675c6dfc_c56b26d3 
PS8, Line 380: static void *new_ish_dir(context *ctx)
> The ISH code seems unrelated to whether things should be in A/B. […]

Ack.

The patch is about PSP layout for A/B. The ISH, which is describe in PSP spec, is part of layout.

And, I admit, it is painful to split.