avformat/movenc: use av_freep() instead of av_free() except for local variables before return

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/movenc.c

@@ -3984,7 +3984,7 @@ static int mov_write_trailer(AVFormatContext *s)
     }
 
     if (mov->chapter_track) {
-        av_free(mov->tracks[mov->chapter_track].enc->extradata);
+        av_freep(&mov->tracks[mov->chapter_track].enc->extradata);
         av_freep(&mov->tracks[mov->chapter_track].enc);
     }
 
@@ -4007,7 +4007,7 @@ static int mov_write_trailer(AVFormatContext *s)
         av_freep(&mov->tracks[i].frag_info);
 
         if (mov->tracks[i].vos_len)
-            av_free(mov->tracks[i].vos_data);
+            av_freep(&mov->tracks[i].vos_data);
     }
 
     av_freep(&mov->tracks);