journal-remote: split-mode=host, remove port from journal filename

journal-remote: split-mode=host, remove port from journal filename

When constructing the journal filename to store logs from a remote host, remove the port of the tcp connection, as the port will change with every reboot/connection loss between sender/reveiver machines. Having the port in the filename will cause a new journal file to be created for every reboot or connection loss.
For the implementation, a new argument "bool include_port" is added to the getpeername_pretty() function. This is passed to the sockaddr_pretty() function. The value of the include_port argument is set to true in all calls of getpeername_pretty(), except for 2 calls in journal-remote.c, where it is set to false.