demux: mp4: compute new pos for audio if blockalign is missing

Prevented playback of blockalign less audio samples

(cherry picked from commit 901cfac0e6b756cc5b0f93bf49e45666dd65d7a7)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/demux/mp4/mp4.c

@@ -3509,7 +3509,8 @@ static uint64_t MP4_TrackGetPos( mp4_track_t *p_track )
         MP4_Box_data_sample_soun_t *p_soun =
             p_track->p_sample->data.p_sample_soun;
 
-        if( p_track->fmt.i_cat != AUDIO_ES || p_soun->i_qt_version == 0 )
+        if( p_track->fmt.i_cat != AUDIO_ES || p_soun->i_qt_version == 0 ||
+            p_track->fmt.audio.i_blockalign <= 1 )
         {
             i_pos += ( p_track->i_sample -
                        p_track->chunk[p_track->i_chunk].i_sample_first ) *
@@ -3518,7 +3519,6 @@ static uint64_t MP4_TrackGetPos( mp4_track_t *p_track )
         else
         {
             /* we read chunk by chunk unless a blockalign is requested */
-            if( p_track->fmt.audio.i_blockalign > 1 )
             i_pos += ( p_track->i_sample - p_track->chunk[p_track->i_chunk].i_sample_first ) /
                         p_soun->i_sample_per_packet * p_soun->i_bytes_per_frame;
         }