The DHCP and OS meta flow setup functions were locking in the wrong
order.  They would try to grab the cn_node_t lock associated with the
dhcp server cn_node_t and the osmeta server cn_node_t first, then do
some flow setup work that would result in the csw lock associated with
both of those nodes being taken.  The order is always csw, cport,
cnode.  So now these functions follow that convention, and things are
happy.

This would typically manifest when a new node was entering from the
metadata server (always from the pending list, as I saw it), and
conflicting with a packet in msg (i.e., an ARP involving the DHCP server
or the OS metadata server).