sockstat: revert incorrect use of path-state for SCTP connections

Revert a change that mistakenly used SCTP path state and the field name
path-state instead of the correct conn-state and sctp_conn_state()
call. This was introduced in 7b35b4d during the addition of libxo
support.

Fixes: 7b35b4d ("sockstat: add libxo support")
Reported by: Phil Shafer <phil@juniper.net>
Sponsored by: Google, LLC (GSoC 2025)
Pull Request: https://github.com/freebsd/freebsd-src/pull
Reviewed by: asomers