Remove unused variable.

modules/demux/mpeg/m4v.c

@@ -70,11 +70,8 @@ static int Open( vlc_object_t * p_this )
     demux_t     *p_demux = (demux_t*)p_this;
     demux_sys_t *p_sys;
     vlc_bool_t   b_forced = VLC_FALSE;
-
     uint8_t     *p_peek;
 
-    es_format_t  fmt;
-
     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
     {
         msg_Err( p_demux, "cannot peek" );