cmake HAVE_VIENNACL_TYPE_TO_STRING examples

shogun-toolbox/shogun cmake/FindViennaCL.cmake :49 

CHECK_CXX_SYMBOL_EXISTS("viennacl::ocl::type_to_string<char>::apply" "viennacl/ocl/utils.hpp" HAVE_VIENNACL_TYPE_TO_STRING)

shogun-toolbox/shogun cmake/FindViennaCL.cmake :64 

elseif (HAVE_VIENNACL_TYPE_TO_STRING)