Remove some deprecated identity options

Below options are deprecated on 2015, so it's safe to delete them now.
  * identity.admin_username
  * auth.admin_tenant_name
  * identity.admin_tenant_name
  * identity.admin_password
  * identity.admin_domain_name

Change-Id: I9cfd3b93f032e6816661e16cbb319af507835997
diff --git a/releasenotes/notes/remove-some-deprecated-identity-options-0ffxd1b8db928e43.yaml b/releasenotes/notes/remove-some-deprecated-identity-options-0ffxd1b8db928e43.yaml
new file mode 100644
index 0000000..e9e9444
--- /dev/null
+++ b/releasenotes/notes/remove-some-deprecated-identity-options-0ffxd1b8db928e43.yaml
@@ -0,0 +1,11 @@
+upgrade:
+  - |
+    Remove deprecated config option ``admin_username`` from
+    ``identity`` groups. Use ``admin_username`` from ``auth`` instead.
+    Remove deprecated config option ``admin_tenant_name`` from
+    ``auth`` and ``identity`` groups. Use ``admin_project_name`` from
+    ``auth`` instead.
+    Remove deprecated config option ``admin_password`` from
+    ``identity`` groups. Use ``admin_password`` from ``auth`` instead.
+    Remove deprecated config option ``admin_domain_name`` from
+    ``identity`` groups. Use ``admin_domain_name`` from ``auth`` instead.
\ No newline at end of file