Such option is more suited to the avcodec-options field and should not be exposed to gui
Signed-off-by: Rafaël Carré <funman@videolan.org>

Fix cid #1048765

This test is always true. Moreover, strrchr does handle empty strings.

This no longer assumes that planes are contiguous. It should help with
libav reference counting, and also avoids interleaving unused padding.

Regression from 5989169a and ticket #7558

Close #9124

Yeah, yeah, such a clever idea, thx...
Let' not use TRACKTOTAL or TOTALTRACKS or TOTALTRACK or TRACKSTOTAL,
because you know, there is not enough options...
Oh, and let's not make ANY of the above official in the spec, because
then, people could follow the spec...
https://www.xiph.org/vorbis/doc/v-comment.html

Next time, please use mkv...

(regression from 46f782a9)

(since the callbacks do not know the actual offsets)