Fix startup so that log prefix %h works for the log_connections message.

We entirely randomly chose to initialize port->remote_host just after
printing the log_connections message, when we could perfectly well do it
just before, allowing %h and %r to work for that message.  Per gripe from
Artem Tomyuk.

Author: tglsfdc

src/backend/postmaster/postmaster.c

@@ -4113,6 +4113,14 @@ BackendInitialize(Port *port)
 	else
 		snprintf(remote_ps_data, sizeof(remote_ps_data), "%s(%s)", remote_host, remote_port);
 
+	/*
+	 * Save remote_host and remote_port in port structure (after this, they
+	 * will appear in log_line_prefix data for log messages).
+	 */
+	port->remote_host = strdup(remote_host);
+	port->remote_port = strdup(remote_port);
+
+	/* And now we can issue the Log_connections message, if wanted */
 	if (Log_connections)
 	{
 		if (remote_port[0])
@@ -4126,12 +4134,6 @@ BackendInitialize(Port *port)
 							remote_host)));
 	}
 
-	/*
-	 * save remote_host and remote_port in port structure
-	 */
-	port->remote_host = strdup(remote_host);
-	port->remote_port = strdup(remote_port);
-
 	/*
 	 * If we did a reverse lookup to name, we might as well save the results
 	 * rather than possibly repeating the lookup during authentication.