Add EVFILT_USER and friends for OpenBSD

OpenBSD -current grew EVFILT_USER. See commit message [1] and and
current sys/event.h [2]

Also EVFILT_DEVICE was missing.

Closes #23930

[1]: https://marc.info/?l=openbsd-cvs&m=174686993115485&w=2
[2]: https://codeberg.org/OpenBSD/src/src/branch/master/sys/sys/event.h
931c6f90f5Evan Silberman committed on 5/22/2025, 2:37:57 AM· committed by Alex Rønne Petersenparenta5861fc
1 file changedLine totals unavailable