iOS/player: reset buffering progress before seeking

ios/IJKMediaPlayer/IJKMediaPlayer/IJKAVMoviePlayerController.m

@@ -337,6 +337,7 @@ static IJKAVMoviePlayerController* instance;
 
     _seekingTime = aCurrentPlaybackTime;
     _isSeeking = YES;
+    _bufferingProgress = 0;
     [self didPlaybackStateChange];
     [self didLoadStateChange];
     if (_isPrerolling) {

ios/IJKMediaPlayer/IJKMediaPlayer/IJKFFMoviePlayerController.m

@@ -519,6 +519,7 @@ inline static int getPlayerOption(IJKFFOptionCategory category)
      postNotificationName:IJKMPMoviePlayerPlaybackStateDidChangeNotification
      object:self];
 
+    _bufferingPosition = 0;
     ijkmp_seek_to(_mediaPlayer, aCurrentPlaybackTime * 1000);
 }