IronicIpVersion: '6' if local_ip is IPv6

Set the ironic pxe version according to the IP version
used on the provisionin network.

Change-Id: I32049dfa892d4f4cdc03dcab2ed31a11abe99770
Closes-Bug: #1845746
Depends-On: I6384e11dd68cdbf2179545caae2c818fd1a6b23e

tripleoclient/tests/v1/undercloud/test_config.py

@@ -201,6 +201,7 @@ class TestNetworkSettings(base.TestCase):
             'MemcachedIPv6': True,
             'RedisIPv6': True,
             'MysqlIPv6': True,
+            'IronicIpVersion': '6',
             'ControlPlaneStaticRoutes': [],
             'IronicInspectorSubnets': [
                 {'gateway': 'fd12:3456:789a:1::1',

tripleoclient/v1/undercloud_config.py

@@ -357,6 +357,7 @@ def _process_network_args(env):
         env['MemcachedIPv6'] = True
         env['RedisIPv6'] = True
         env['MysqlIPv6'] = True
+        env['IronicIpVersion'] = '6'
 
     # We do not use undercloud ips for env, but just validate the configured
     # value here.