Change in coreboot[master]: amdfwtool: Add options to separate signed firmwares

[Kangheui Won (Code Review)]

Attention is currently required from: Jason Glenesk, Marshall Dawson, Karthik Ramasubramanian, Felix Held.
Hello Jason Glenesk, build bot (Jenkins), Marshall Dawson, Karthik Ramasubramanian, Felix Held,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/59866

to look at the new patch set (#3).

Change subject: amdfwtool: Add options to separate signed firmwares
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amdfwtool: Add options to separate signed firmwares

Add support for separating signed firmwares into another file.

If sig_opt in file header is 1 it means that the firmware is signed by
AMD and will be verified by the PSP. If we put them outside FW_MAIN_[AB]
we can skip vboot verification on them, improving overall verification
time.

BUG=b:206909680
TEST=build amdfwtool

Signed-off-by: Kangheui Won 
Change-Id: I9f3610a7002b2a9c70946b083b0b3be6934200b0
---
M util/amdfwtool/amdfwtool.c
M util/amdfwtool/amdfwtool.h
2 files changed, 172 insertions(+), 9 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/66/59866/3