Ensure link is set to up, when moving IP addresses across interfaces.

- To add, initialize and set up a valiable named IP_UP
 - To bring up interface after moving IP to OVS bridge

Change-Id: I70f5974c115be6f7e7422a9a325f36cf3b71455a
Closes-Bug: #1469596

lib/neutron-legacy

@@ -798,6 +798,7 @@ function _move_neutron_addresses_route {
 
         local IP_ADD=""
         local IP_DEL=""
+        local IP_UP=""
         local DEFAULT_ROUTE_GW
         DEFAULT_ROUTE_GW=$(ip r | awk "/default.+$from_intf/ { print \$3; exit }")
         local ADD_OVS_PORT=""
@@ -821,9 +822,10 @@ function _move_neutron_addresses_route {
         if [[ "$IP_BRD" != "" ]]; then
             IP_DEL="sudo ip addr del $IP_BRD dev $from_intf"
             IP_ADD="sudo ip addr add $IP_BRD dev $to_intf"
+            IP_UP="sudo ip link set $to_intf up"
         fi
 
-        $IP_DEL; $IP_ADD; $ADD_OVS_PORT; $ADD_DEFAULT_ROUTE
+        $IP_DEL; $IP_ADD; $IP_UP; $ADD_OVS_PORT; $ADD_DEFAULT_ROUTE
     fi
 }