mms: Remove non-utf8 characters

Certain softwares get badly confused.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

libavformat/mms.c

 /*
  * MMS protocol common definitions.
  * Copyright (c) 2006,2007 Ryan Martell
- * Copyright (c) 2007 Bjrn Axelsson
+ * Copyright (c) 2007 Björn Axelsson
  * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com>
  *
  * This file is part of Libav.

libavformat/mmst.c

 /*
  * MMS protocol over TCP
  * Copyright (c) 2006,2007 Ryan Martell
- * Copyright (c) 2007 Bjrn Axelsson
+ * Copyright (c) 2007 Björn Axelsson
  * Copyright (c) 2010 Zhentan Feng <spyfeng at gmail dot com>
  *
  * This file is part of Libav.