Disable revoke_by_id in keystone

revoke api is only used when using kvs revoke driver. In most of case it
is useless and unnecessary.

Change-Id: I6afaf32574330e3ee57435f688c41ae74dbdf7ed
Closes-Bug: #1664026

ansible/roles/keystone/templates/keystone.conf.j2

@@ -21,6 +21,7 @@ domain_config_dir = /etc/keystone/domains
 {% endif %}
 
 [token]
+revoke_by_id = False
 {% if keystone_token_provider == 'uuid' %}
 provider = uuid
 {% elif keystone_token_provider == 'fernet' %}