Updating files for missing licenses (#637)

[ROCm/rccl commit: ebb8b5bf63]

projects/rccl/test/common/PtrUnion.cpp

@@ -1,3 +1,9 @@
+/*************************************************************************
+ * Copyright (c) 2022 Advanced Micro Devices, Inc. All rights reserved.
+ *
+ * See LICENSE.txt for license information
+ ************************************************************************/
+
 #include "PtrUnion.hpp"
 
 namespace RcclUnitTesting