12168 mDNSResponder update to mDNSResponder-878.260.1
Reviewed by: Ken Mays <kmays2000@gmail.com>
Approved by: Robert Mustacchi <rm@fingolfin.org>

8886 mdns: update to mDNSResponder-878.1.1
Reviewed by: Gergő Mihály Doma <domag02@gmail.com>
Reviewed by: Andy Fiddaman <af@citrus-it.net>
Approved by: Robert Mustacchi <rm@joyent.com>