Remove extraneous "n" from comment in routerset.c

src/feature/nodelist/routerset.c

@@ -1,5 +1,5 @@
 /* Copyright (c) 2001 Matej Pfajfar.
-n * Copyright (c) 2001-2004, Roger Dingledine.
+ * Copyright (c) 2001-2004, Roger Dingledine.
  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
  * Copyright (c) 2007-2019, The Tor Project, Inc. */
 /* See LICENSE for licensing information */