MLBEDSW-6620: Update copyright notice and years

- Update copyright notices to use SPDX format and add OSS mail as contact.
- Update years on files where it had been missed.

Signed-off-by: Rickard Bolin <rickard.bolin@arm.com>
Change-Id: I7e9715ea4e17b76252728c708e46df12ad67ab1f
diff --git a/ethosu/mlw_codec/mlw_common.h b/ethosu/mlw_codec/mlw_common.h
index 008473a..70f72de 100644
--- a/ethosu/mlw_codec/mlw_common.h
+++ b/ethosu/mlw_codec/mlw_common.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020 Arm Limited. All rights reserved.
+ * SPDX-FileCopyrightText: Copyright 2020 Arm Limited and/or its affiliates <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: Apache-2.0
  *