libvlc: fix libvlc_video_set_track()

When we set the video track, we probably be wanting to change video-es vars instead of audio-es
(cherry picked from commit e1abfdca)
Signed-off-by: Derk-Jan Hartman <hartman@videolan.org>

src/control/video.c

@@ -735,7 +735,7 @@ void libvlc_video_set_track( libvlc_media_player_t *p_mi, int i_track,
         vlc_value_t val = val_list.p_list->p_values[i];
         if( i_track == val.i_int )
         {
-            i_ret = var_Set( p_input_thread, "audio-es", val );
+            i_ret = var_Set( p_input_thread, "video-es", val );
             if( i_ret < 0 )
                 libvlc_exception_raise( p_e, "Setting video track failed" );
             goto end;