Bug#828451: Upstream are aware but stuck

[debian at fau.xxx]

Upstream are aware of this issue, but quite stuck on it, by the look of
it:

 * https://github.com/netty/netty-tcnative/issues/263
 * https://github.com/netty/netty/issues/6320

This is going to be a problem, as netty-tcnative can't be removed from
testing, as it chains to fop, which half the world build-deps on for docs.

 * netty-tcnative
 * netty
 * jython
 * batik
 * fop
 * half the world