MLECO-3583: Update copyright notice according to new guidelines

Change-Id: I0f057b33993e5196a60e52f4fb0c60e09693dcfe
diff --git a/.clang-format b/.clang-format
index d53ffa1..192a0a5 100644
--- a/.clang-format
+++ b/.clang-format
@@ -1,5 +1,5 @@
 #
-# Copyright (c) 2022 Arm Limited. All rights reserved.
+# SPDX-FileCopyrightText: Copyright 2022 Arm Limited and/or its affiliates <open-source-office@arm.com>
 #
 # SPDX-License-Identifier: Apache-2.0
 #