lz4: Update our internal copy to release r128
Looking through the git log it is unclear which release we used before as nobody
stated it there. :/ We updated after the security issues last year so my best
guess is that we have something like r119.
I recommend STRONGLY that you check if your distro ships liblz4 as an up to
date library package and use the --enable-liblz4 configure option to use the
system version. I consider making the system version default for upcoming
releases and only carry the internal one as fallback for systems that do not