Updating copyright notices for 2020.

src/collectives/device/all_reduce.h

@@ -1,6 +1,6 @@
 /*************************************************************************
  * Copyright (c) 2015-2019, NVIDIA CORPORATION. All rights reserved.
- * Modifications Copyright (c) 2019 Advanced Micro Devices, Inc. All rights reserved.
+ * Modifications Copyright (c) 2019-2020 Advanced Micro Devices, Inc. All rights reserved.
  *
  * See LICENSE.txt for license information
  ************************************************************************/