net-p2p/libutp: update to g20230213

In preparation of the following net-p2p/transmission update.
The library must be updated in lockstep.

PR: 269504
Reported by: dutchman01@quicknet.nl
Approved by: rigoletto, tcberner (maintainer timeout)
Reviewed By: fcharlier_ploup.net
Differential Revision: https://reviews.freebsd.org/D40910