fftools/ffmpeg_demux: drop InputStream.[nb_]outputs

It is write-only after d119ae2fd8.

fftools/ffmpeg.h

@@ -463,14 +463,6 @@ typedef struct InputStream {
      * currently video and audio only */
     InputFilter         **filters;
     int                nb_filters;
-
-    /*
-     * Output targets that do not go through lavfi, i.e. subtitles or
-     * streamcopy. Those two cases are distinguished by the OutputStream
-     * having an encoder or not.
-     */
-    struct OutputStream **outputs;
-    int                nb_outputs;
 } InputStream;
 
 typedef struct InputFile {

fftools/ffmpeg_demux.c

@@ -840,7 +840,6 @@ static void ist_free(InputStream **pist)
 
     av_dict_free(&ds->decoder_opts);
     av_freep(&ist->filters);
-    av_freep(&ist->outputs);
     av_freep(&ds->dec_opts.hwaccel_device);
 
     avcodec_parameters_free(&ist->par);
@@ -985,12 +984,6 @@ int ist_output_add(InputStream *ist, OutputStream *ost)
     if (ret < 0)
         return ret;
 
-    ret = GROW_ARRAY(ist->outputs, ist->nb_outputs);
-    if (ret < 0)
-        return ret;
-
-    ist->outputs[ist->nb_outputs - 1] = ost;
-
     return ost->enc ? ds->sch_idx_dec : ds->sch_idx_stream;
 }