demux_disc: bluray: fix stream language (2)

Commit 50e131b43e happened to make it work for DVD (because the higher
bits of the ID are masked in the DVD case), but failed for Bluray. This
probably fixes it, although I don't have a sample to multiple streams to
confirm it really does it right.

CC: @mpv-player/stable

demux/demux_disc.c

@@ -143,6 +143,7 @@ static void add_streams(demuxer_t *demuxer)
         sh->codec = talloc_strdup(sh, src->codec);
         sh->format = src->format;
         sh->lav_headers = src->lav_headers;
+        sh->demuxer_id = src->demuxer_id;
         if (src->video) {
             double ar;
             if (stream_control(demuxer->stream, STREAM_CTRL_GET_ASPECT_RATIO, &ar)