MEDIUM: server: do not restrict anymore usage of IP address from the state file

MEDIUM: server: do not restrict anymore usage of IP address from the state file

Now that it is possible to decide whether we prefer to use libc or the
state file to resolve the server's IP address and it is possible to change
a server's IP address at run time on the CLI, let's not restrict the reuse
of the address from the state file anymore to the DNS only.

The impact is that by default the state file will be considered first
(which matches its purpose) and only then the libc. This way any address
change performed at run time over the CLI will be preserved regardless
of DNS usage or not.