So setting up logging for ctrld binary and ctrld packages could be done
more easily, decouple the required setup for interactive vs daemon
running.
This is the first step toward replacing rs/zerolog libary with a
different logging library.
An interface may have multiple MAC addresses, that leads to the problem
when looking up hostname for its multiple <ip, mac> pairs, because the
"ip" map, which storing "mac => ip" mapping can only store 1 entry. It
ends up returns an empty hostname for a known MAC address.
Fixing this by filling empty hostname based on clients which is already
listed, ensuring all clients with the same MAC address will have the
same hostname information.