Remove transition logic for old tempest option renaming

This logic was required to adopt to the renaming in tempest[1] which
was done in 12.0.0 release. Now the minimum tempest version required
is much higher so we no longer need this compatibility consideration.

[1] ed6e586b9f8f0ada10af7711f297afa01b2b7754

Change-Id: I5d13f9146b00b2fcd5c2e96071ab914b8a56a089
diff --git a/neutron_tempest_plugin/api/base.py b/neutron_tempest_plugin/api/base.py
index e17cf5e..4bcc6d2 100644
--- a/neutron_tempest_plugin/api/base.py
+++ b/neutron_tempest_plugin/api/base.py
@@ -595,15 +595,11 @@
             # Generate subnet CIDRs starting from configured values
             ip_version = ip_version or cls._ip_version
             if ip_version == const.IP_VERSION_4:
-                mask_bits = mask_bits or config.safe_get_config_value(
-                    'network', 'project_network_mask_bits')
-                cidr = netaddr.IPNetwork(config.safe_get_config_value(
-                    'network', 'project_network_cidr'))
+                mask_bits = mask_bits or CONF.network.project_network_mask_bits
+                cidr = netaddr.IPNetwork(CONF.network.project_network_cidr)
             elif ip_version == const.IP_VERSION_6:
-                mask_bits = config.safe_get_config_value(
-                    'network', 'project_network_v6_mask_bits')
-                cidr = netaddr.IPNetwork(config.safe_get_config_value(
-                    'network', 'project_network_v6_cidr'))
+                mask_bits = CONF.network.project_network_v6_mask_bits
+                cidr = netaddr.IPNetwork(CONF.network.project_network_v6_cidr)
             else:
                 raise ValueError('Invalid IP version: {!r}'.format(ip_version))
 
diff --git a/neutron_tempest_plugin/api/test_routers.py b/neutron_tempest_plugin/api/test_routers.py
index 7758b1a..1430b81 100644
--- a/neutron_tempest_plugin/api/test_routers.py
+++ b/neutron_tempest_plugin/api/test_routers.py
@@ -38,9 +38,9 @@
     def resource_setup(cls):
         super(RoutersTest, cls).resource_setup()
         cls.tenant_cidr = (
-            config.safe_get_config_value('network', 'project_network_cidr')
+            CONF.network.project_network_cidr
             if cls._ip_version == 4 else
-            config.safe_get_config_value('network', 'project_network_v6_cidr'))
+            CONF.network.project_network_v6_cidr)
 
     @decorators.idempotent_id('c72c1c0c-2193-4aca-eeee-b1442640eeee')
     @tutils.requires_ext(extension="standard-attr-description",
diff --git a/neutron_tempest_plugin/config.py b/neutron_tempest_plugin/config.py
index 55d9d9e..23757c1 100644
--- a/neutron_tempest_plugin/config.py
+++ b/neutron_tempest_plugin/config.py
@@ -259,19 +259,3 @@
     name='designate_feature_enabled', title='Enabled Designate Features')
 CONF.register_group(dns_feature_group)
 CONF.register_opts(DnsFeatureGroup, group="designate_feature_enabled")
-
-config_opts_translator = {
-    'project_network_cidr': 'tenant_network_cidr',
-    'project_network_v6_cidr': 'tenant_network_v6_cidr',
-    'project_network_mask_bits': 'tenant_network_mask_bits',
-    'project_network_v6_mask_bits': 'tenant_network_v6_mask_bits'}
-
-
-def safe_get_config_value(group, name):
-    """Safely get Oslo config opts from Tempest, using old and new names."""
-    conf_group = getattr(CONF, group)
-
-    try:
-        return getattr(conf_group, name)
-    except cfg.NoSuchOptError:
-        return getattr(conf_group, config_opts_translator[name])