Improves and cleanups over inetd(8):

• Teach inetd(8) about kqueue, originally implemented by jmg@[1].
• Use new C99 style function prototypes instead of K&Rs.
• Raise WARNS from 2 to 6

Glanced at by: ru
MFC After: 2 weeks

[1] http://people.freebsd.org/~jmg/inetd.kq.patch,

http://people.freebsd.org/~jmg/inetd.kq.html