[neutron] 'up' interfaces added via ovs auto_bridge_add

Previously, when adding interfaces to an ovs bridge we would set the
link state to up.  Some environments assume this is the case so
restore that behavior.

This fixes the problem where external (public) IPs for routers and VMs
no longer respond.

Change-Id: I59e21bd5cde7e239320125e9a7e0a33adae578a8

neutron/templates/bin/_neutron-openvswitch-agent-init.sh.tpl

@@ -45,6 +45,7 @@ do
   if [ -n "$iface" ] && [ "$iface" != "null" ]
   then
     ovs-vsctl --no-wait --may-exist add-port $bridge $iface
+    ip link set dev $iface up
   fi
 done