Merge branch 'vectorize_rm_unused' into 'main'

rm unused ATH_ENABLE_FUNCTION_VECTORIZATION

See merge request !66497

Control/CxxUtils/CxxUtils/vectorize.h

 // This file's extension implies that it's C, but it's really -*- C++ -*-.
 /*
- * Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration.
+ * Copyright (C) 2002-2023 CERN for the benefit of the ATLAS collaboration.
  */
 /**
  * @file CxxUtils/vectorize.h
@@ -33,11 +33,4 @@
 # define ATH_ENABLE_VECTORIZATION class ATH_ENABLE_VECTORIZATION_SWALLOW_SEMICOLON
 #endif
 
-#if defined(__GNUC__) && !defined(__clang__) && !defined(__ICC) && !defined(__COVERITY__) &&  \
-  !defined(__CUDACC__)
-# define ATH_ENABLE_FUNCTION_VECTORIZATION __attribute__((optimize("tree-vectorize")))
-#else
-# define ATH_ENABLE_FUNCTION_VECTORIZATION
-#endif
-
 #endif // not CXXUTILS_VECTORIZE_H