[M] Change in coreboot[master]: build: List all Kconfigs in CBFS `config` file, compress it

[Nico Huber (Code Review)]

Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/69710 )

Change subject: build: List all Kconfigs in CBFS `config` file, compress it
......................................................................

Patch Set 3:

(1 comment)

Patchset:

PS3:
> The intention was that you can do everything with this new file that you could do with the old

Technically, the new use case was already possible, just needed additional steps.
So it's a matter of convenience. We can't have the same convenience for all use
cases with a single solution, AFAICT.

Originally, if one wanted to grep for a config, one had to run `make olddefconfig`
first.

With the fixed, new solution, if one wants to see which options differ
from defaults (a common case when providing user support), one has to run
`make olddefconfig && make savedefconfig`.

I guess there'll always be a use case that isn't easy. That could be mitigated
with a script maybe?