Move comment to a slightly better place.

Originally committed as revision 9462 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavutil/aes.c

 /*
  * copyright (c) 2007 Michael Niedermayer <michaelni@gmx.at>
  *
+ * some optimization ideas from aes128.c by Reimar Doeffinger
+ *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
@@ -16,8 +18,6 @@
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * some optimization ideas from aes128.c by Reimar Doeffinger
  */
 
 #include "common.h"