Add my name to the copyright header, since rtp_mpv now contains

a fair amount of code written by me

Originally committed as revision 10563 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/rtp_mpv.c

 /*
  * RTP packetization for MPEG video
  * Copyright (c) 2002 Fabrice Bellard.
+ * Copyright (c) 2007 Luca Abeni.
  *
  * This file is part of FFmpeg.
  *