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.

src/socket-proxy/socket-proxyd.c

@@ -505,7 +505,7 @@ static int accept_cb(sd_event_source *s, int fd, uint32_t revents, void *userdat
                 if (errno != -EAGAIN)
                         log_warning_errno(errno, "Failed to accept() socket: %m");
         } else {
-                getpeername_pretty(nfd, &peer);
+                getpeername_pretty(nfd, true, &peer);
                 log_debug("New connection from %s", strna(peer));
 
                 r = add_connection_socket(context, nfd);