fixed build issues with FFMpeg AVCodec version >=59 changes (#636)

* fixed build issues with FFMpeg AVCodec version >=59 changes

* fixed mistake of pushing stashed change

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Co-authored-by: Kiriti Gowda <kiritigowda@gmail.com>

utils/video_demuxer.h

@@ -462,7 +462,11 @@ class VideoDemuxer {
                         || !strcmp(av_fmt_input_ctx_->iformat->long_name, "Matroska / WebM"));
 
             // Check if the input file allow seek functionality.
+#if USE_AVCODEC_GREATER_THAN_58_134
+            is_seekable_ = true;    //for latest version of FFMPeg, read_seek and read_seek2 is not exposed in AVFormatContext
+#else            
             is_seekable_ = av_fmt_input_ctx_->iformat->read_seek || av_fmt_input_ctx_->iformat->read_seek2;
+#endif            
 
             if (is_h264_) {
                 const AVBitStreamFilter *bsf = av_bsf_get_by_name("h264_mp4toannexb");