Move the convert_sigevent32() utility function into freebsd32_misc.c
for consumption outside the vfs_aio.c.

For SIGEV_THREAD_ID and SIGEV_SIGNAL notification delivery methods,
also copy in the sigev_value, since librt event pumping loop compares
note generation number with the value passed through sigev_value.

Tested by:	Petr Salinger <Petr.Salinger@seznam.cz>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
The freebsd32_lio_listio() compat syscall takes the struct sigevent32.

Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Wrap kmq_notify(2) for compat32 to properly consume struct sigevent32
argument.

Reviewed and tested by:	Petr Salinger <Petr.Salinger@seznam.cz>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Implement compat32 wrappers for the ktimer_* syscalls.

Reported, reviewed and tested by:	Petr Salinger <Petr.Salinger@seznam.cz>
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Regenerate.