[3.0] deinterlace: remove always false b_half_height variable
Even in 3.0 it's never set to true.
Fixes #28952 (closed)
(cherry picked from commit fbbd68f8) (edited)
edited:
- on 3.0 the callback is set on the filter_t structure
- on 3.0 the old and new pointer values are passed to the callback