x11/xfindproxy, x11/xfwp: Deprecate

Deprecate x11/xfindproxy and x11/xfwp, they are deprecated upstream.
Make the deprecation timer extra short, since these ports are in the way of
other updates on x11 land.

PR: 241314 (related)
MFH: 2019Q4 (do we MFH deprecation notices?)