[ownership] Add a dummy owner

The `dummy` owner is a secondary owner used for testing ownership
transfer flows.

Signed-off-by: Chris Frantz <cfrantz@google.com>
(cherry picked from commit e5c2899)
(cherry picked from commit ba2766f)

sw/device/silicon_creator/lib/ownership/keys/dummy/BUILD

@@ -0,0 +1,30 @@
+# Copyright lowRISC contributors (OpenTitan project).
+# Licensed under the Apache License, Version 2.0, see LICENSE for details.
+# SPDX-License-Identifier: Apache-2.0
+
+package(default_visibility = ["//visibility:public"])
+
+filegroup(
+    name = "owner_key",
+    srcs = ["owner_ecdsa_p256.der"],
+)
+
+filegroup(
+    name = "activate_key",
+    srcs = ["activate_ecdsa_p256.der"],
+)
+
+filegroup(
+    name = "unlock_key",
+    srcs = ["unlock_ecdsa_p256.der"],
+)
+
+filegroup(
+    name = "app_prod",
+    srcs = ["app_prod_rsa_3072_exp_f4.der"],
+)
+
+filegroup(
+    name = "app_prod_pub",
+    srcs = ["app_prod_rsa_3072_exp_f4.pub.der"],
+)