bsd-user: Fix syscall format, add strace support for more syscalls

Conflicts:
	bsd-user/freebsd/strace.list
bsd-user: Implement strace support for thr_* syscalls

Conflicts:
	bsd-user/freebsd/strace.list
bsd-user: Implement strace support for __acl_* syscalls

Conflicts:
	bsd-user/freebsd/strace.list