[HIP][tests] Copyright notice update

hipamd/samples/2_Cookbook/1_hipEvent/hipEvent.cpp

@@ -1,5 +1,5 @@
 /*
-Copyright (c) 2015-2016 Advanced Micro Devices, Inc. All rights reserved.
+Copyright (c) 2015-present Advanced Micro Devices, Inc. All rights reserved.
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal