Use SPDX identifiers

SPDX identifiers are simpler, and reduce the amount of cruft we have in
code files.  They are recommended by linux foundation, and therefore we
should do as they allow.

This patchset does not intend to modify any intent on any existing
copyrights or licenses, only to standardize their inclusion.

[1] https://www.linuxfoundation.org/blog/blog/copyright-notices-in-open-source-software-projects

Change-Id: I935c7c0156caa78fc368c929cebd0f068031e830
Signed-off-by: Ed Tanous <etanous@nvidia.com>
diff --git a/redfish-core/lib/power.hpp b/redfish-core/lib/power.hpp
index 6ce95bd..a221d72 100644
--- a/redfish-core/lib/power.hpp
+++ b/redfish-core/lib/power.hpp
@@ -1,19 +1,8 @@
-/*
-Copyright (c) 2018 Intel Corporation
-Copyright (c) 2018 Ampere Computing LLC
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: Copyright OpenBMC Authors
+// SPDX-FileCopyrightText: Copyright 2018 Intel Corporation
+// SPDX-FileCopyrightText: Copyright 2018 Ampere Computing LLC
 
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-      http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
 #pragma once
 
 #include "app.hpp"