lib-smtp: server: STARTTLS command: Call smtp_server_connection_set_s…

…sl_streams() after calling the conn_start_tls() connection callback.

This is called instead smtp_server_connection_set_streams(), so that the connection is now marked as SSL-secured.
This fixes a submission-login bug that prevented client login when ssl=required.

src/lib-smtp/smtp-server-cmd-starttls.c

@@ -30,7 +30,7 @@ static int cmd_starttls_start(struct smtp_server_connection *conn)
 		if (!smtp_server_connection_unref(&tmp_conn) || ret < 0)
 			return -1;
 
-		smtp_server_connection_set_streams(conn, input, output);
+		smtp_server_connection_set_ssl_streams(conn, input, output);
 	} else if (smtp_server_connection_ssl_init(conn) < 0) {
 		smtp_server_connection_close(&conn,
 			"SSL Initialization failed");