Change from using poll(2) to kqueue/kevent when waiting for a DNS response to return.  This will stop processes waiting on DNS requests from being woken up when a select collision occurs.  This was tested on mx1.FreeBSD.org (outgoing mail for the FreeBSD.org mailing lists.)
Change from using poll(2) to kqueue/kevent when waiting for a DNS
response to return.  This will stop processes waiting on DNS requests
from being woken up when a select collision occurs.  This was tested
on mx1.FreeBSD.org (outgoing mail for the FreeBSD.org mailing
lists.)

Reviewed by:	jlemon, peter

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase