`inet_listener_reuse_port` is undocumented

[allan2]

It looks like inet_listener_reuse_port is undocumented.

1. https://doc.dovecot.org/2.4.2/core/config/service.html#inet_listener
2. https://github.com/dovecot/core/blob/13ac9959a3c399e8a9d53f40f7858109dc0801f3/src/lib-master/service-settings.h#L43-L52