Change in flashrom[master]: layout: Add -i <region>[:<file>] support

[Sam McNally (Code Review)]

Attention is currently required from: Nico Huber, Nicola Corna, Jack Rosenthal, Paul Menzel, Stefan Reinauer, David Hendricks, Daniel Campello, Arthur Heymans, Carl-Daniel Hailfinger.
Sam McNally has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/23021 )

Change subject: layout: Add -i <region>[:<file>] support
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Patch Set 35: Code-Review+2

(1 comment)

File flashrom.c:

https://review.coreboot.org/c/flashrom/+/23021/comment/7c03ecda_9a616a2f 
PS35, Line 1493: #ifdef __LIBPAYLOAD__
It feels a bit weird for write_buf_to_include_args() to fail eagerly for __LIBPAYLOAD__ while read_buf_from_include_args() does not.

As far as I can tell, it doesn't have any meaningful effect since the first (read|write)_buf_(from|to)_file will fail in that configuration anyway (so read codepaths will never reach read_buf_from_include_args()), but it feels like an unnecessary difference requiring a little bit of digging to understand.