Adds network check in upgrade phase in devstack

When running grenade with multitenancy, we are able to boot instances
in the network neutron has created in its upgrade phase, and we don't
have to change that setup.

Change-Id: I1038548ad4f93788fca3e2b7dd8ed93da0ce7702

devstack/upgrade/resources.sh

@@ -33,6 +33,11 @@ set -o xtrace
 
 
 function early_create {
+    # We need these steps only in case of flat-network
+    if [[ -n "${IRONIC_PROVISION_NETWORK_NAME}" ]]; then
+        return
+    fi
+
     # Ironic needs to have network access to the instance during deployment
     # from the control plane (ironic-conductor). This 'early_create' function
     # creates a new network with a unique CIDR, adds a route to this network
@@ -98,6 +103,11 @@ function verify_noapi {
 }
 
 function destroy {
+    # We need these steps only in case of flat-network
+    if [[ -n "${IRONIC_PROVISION_NETWORK_NAME}" ]]; then
+        return
+    fi
+
     # NOTE(vsaienko) move ironic VMs back to private network.
     local net_id
     net_id=$(openstack network show private -f value -c id)

devstack/upgrade/upgrade.sh

@@ -86,11 +86,14 @@ start_nova_compute
 ensure_services_started ironic-api ironic-conductor
 ensure_logs_exist ir-cond ir-api
 
+# We need these steps only in case of flat-network
 # NOTE(vsaienko) starting from Ocata when Neutron is restarted there is no guarantee that
 # internal tag, that was assigned to network will be the same. As result we need to update
 # tag on link between br-int and brbm to new value after restart.
+if [[ -z "${IRONIC_PROVISION_NETWORK_NAME}" ]]; then
     net_id=$(openstack network show ironic_grenade -f value -c id)
     create_ovs_taps $net_id
+fi
 
 set +o xtrace
 echo "*********************************************************************"