Add placement service in 'enforce_scope' config

Adding placement service in 'enforce_scope' config
so that we can switch the placement scope and new defaults
and test them.

Change-Id: Ie9a4c22dee892eae84f35af2b6b5ff2098225495

releasenotes/notes/enforce_scope_placement-47a12c741e330f60.yaml

@@ -0,0 +1,4 @@
+---
+prelude: >
+    Adding placement service for config options ``enforce_scope`` so that
+    we can switch the scope and new defaults enforcement for placement service.

tempest/config.py

@@ -1280,6 +1280,13 @@ EnforceScopeGroup = [
                      'enabled when keystone.conf: [oslo_policy]. '
                      'enforce_new_defaults and keystone.conf: [oslo_policy]. '
                      'enforce_scope options are enabled in keystone conf.'),
+    cfg.BoolOpt('placement',
+                default=False,
+                help='Does the placement service API policies enforce scope '
+                     'and new defaults? This configuration value should be '
+                     'enabled when placement.conf: [oslo_policy]. '
+                     'enforce_new_defaults and nova.conf: [oslo_policy]. '
+                     'enforce_scope options are enabled in placement conf.'),
 ]
 
 debug_group = cfg.OptGroup(name="debug",