input: remove dead and broken byte offset bookmark support (refs #8455)
Nobody would use this in real life (even time offset bookmarks are hardly used at all), the "feature" was unreachable from the UI, and it does not work with most demuxers. seekpoint_t.i_byte_offset is kept due to other usage of the same structure, i.e. proper seek points (as opposed to bookmarks).
Showing with 6 additions and 24 deletions