[coreboot] Problems building coreboot 4.6 (was: problems with kgpe-d16)

[Julius Werner]

> The error is fixed by commit
> 54fd92bc (util/cbfstool/lz4frame.c: Add comment to fall through).

Looks like I'm too late for that commit, but in general, please do not
just hack around in the LZ4 files. That code was pulled in verbatim
from the upstream source -- if there are issues with it, please
instead send a patch to https://github.com/lz4/lz4 and resync our code
base to there once it has landed.