10l: remove alien seek function from demuxer

Originally committed as revision 6617 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/wv.c

@@ -205,5 +205,4 @@ AVInputFormat wv_demuxer = {
     wv_read_header,
     wv_read_packet,
     wv_read_close,
-    pcm_read_seek,
 };