Log Message:
libfilezilla: update to 0.40.0.

0.40.0 (2022-12-12)

+ Added fz::unicode_codepoint_to_utf8_append
+ Added fz::strtokenizer
+ Added fz::check_certificate_status

0.39.2 (2022-10-11)

- Fixed removing aio_waiters/event_handlers from aio_waitable
- Fixed start offset in view_reader
- Fix buffer_writer not releasing added buffers

0.39.1 (2022-09-12)

- MSW: Fixed a possible hang in fz::process:kill

0.39.0 (2022-09-05)

+ Added readwrite mode to fz::file.
+ MSW: Added fz::dll and fz::shdlls glue
+ Added fz::ascii_layer
- *nix: Fixed mmap error handling in fz::aio_buffer_pool
- Fixed a potential deadlock in the aio code
- Fixed an issue with calling conventions on 32bit Windows
- MSW: fz::datetime::get_tm now works for dates past Y2K38 on toolchains with \ 
32bit time_t
- MSW: Fixed an error reading from fz::process