Commit
248b50681057f7f1b9abe409548de2764a958b5e
by Pau Espin PedrolPort pfcp socket to osmo_iofd
As a indirect consequence, the pfcp socket now earns a Tx queue, which
should avoid sporadic tx msg drops during high load.
Related: OS#6714
Change-Id: If85888b6857899e0aca1fdd1d806c53476b4d239