fftools/ffmpeg: Remove unused fields

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

fftools/ffmpeg.h

@@ -360,8 +360,6 @@ typedef struct InputStream {
         unsigned int initialize; ///< marks if sub2video_update should force an initialization
     } sub2video;
 
-    int dr1;
-
     /* decoded data from this stream goes into all those filters
      * currently video and audio only */
     InputFilter **filters;
@@ -413,7 +411,6 @@ typedef struct InputFile {
     int64_t ts_offset;
     int64_t last_ts;
     int64_t start_time;   /* user-specified start time in AV_TIME_BASE or AV_NOPTS_VALUE */
-    int seek_timestamp;
     int64_t recording_time;
     int nb_streams;       /* number of stream that ffmpeg is aware of; may be different
                              from ctx.nb_streams if new streams appear during av_read_frame() */