[coreboot-gerrit] Change in coreboot[master]: fw_config: Add firmware configuration interface

[Duncan Laurie (Code Review)]

Duncan Laurie has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/41209 )

Change subject: fw_config: Add firmware configuration interface
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Patch Set 1:

I try to avoid introducing new top-level interfaces if possible, but to do probing it really needs integration in both drivers and mainboards and it seemed that src/lib was the best location.

I decided to follow the naming that was used when defining this interface in the EC and the factory process so it would be clear when working with coreboot what it affects.  That said 'firmware configuration' is a pretty generic term and there may be other opinions on how to name it.

The first board to use this interface is volteer, but it will get added for other new boards soon.