remove double check of pb->read_seek

Originally committed as revision 11278 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/asf.c

@@ -1050,10 +1050,11 @@ static int asf_read_seek(AVFormatContext *s, int stream_index, int64_t pts, int
         return -1;
 
     /* Try using the protocol's read_seek if available */
-    if(s->pb && s->pb->read_seek) {
+    if(s->pb) {
         int ret = av_url_read_fseek(s->pb, stream_index, pts, flags);
         if(ret >= 0)
             asf_reset_header(s);
+        if (ret != AVERROR(ENOSYS))
         return ret;
     }
 

libavformat/utils.c

@@ -2042,7 +2042,7 @@ int av_read_play(AVFormatContext *s)
 {
     if (s->iformat->read_play)
         return s->iformat->read_play(s);
-    if (s->pb && s->pb->read_pause)
+    if (s->pb)
         return av_url_read_fpause(s->pb, 0);
     return AVERROR(ENOSYS);
 }
@@ -2051,7 +2051,7 @@ int av_read_pause(AVFormatContext *s)
 {
     if (s->iformat->read_pause)
         return s->iformat->read_pause(s);
-    if (s->pb && s->pb->read_pause)
+    if (s->pb)
         return av_url_read_fpause(s->pb, 1);
     return AVERROR(ENOSYS);
 }