Change in coreboot[master]: lib/future: Implement Futures API

[Martin Roth (Code Review)]

Attention is currently required from: Raul Rangel, Aaron Durbin, Furquan Shaikh, Marshall Dawson, Julius Werner, Eric Peers.
Martin Roth has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/56048 )

Change subject: lib/future: Implement Futures API
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Patch Set 4:

(2 comments)

File src/lib/Kconfig:

https://review.coreboot.org/c/coreboot/+/56048/comment/f4fe6dbc_43383781 
PS2, Line 103: bool
> Add a prompt so it can be disabled for debug?

After talking with Raul, it seems like disabling the feature at this level doesn't really make sense.  If individual features make use of this, they might not have the ability to fall back to an alternative method.

File src/lib/Makefile.inc:

https://review.coreboot.org/c/coreboot/+/56048/comment/56da5d04_70ef61a0 
PS2, Line 274: -y
> Make dependent on the config option being enabled?

After talking with Raul, it seems like disabling the feature at this level doesn't really make sense.  If individual features make use of this, they might not have the ability to fall back to an alternative method.