Updated macro name

Author: JackAKirk

sycl/include/CL/sycl/feature_test.hpp.in

@@ -55,7 +55,7 @@ namespace sycl {
 #define SYCL_EXT_ONEAPI_SUB_GROUP 1
 #define SYCL_EXT_ONEAPI_PROPERTIES 1
 #define SYCL_EXT_ONEAPI_NATIVE_MATH 1
-#define SYCL_EXT_ONEAPI_BF16_CONVERSION 1
+#define SYCL_EXT_ONEAPI_BFLOAT16 1
 #define SYCL_EXT_INTEL_DATAFLOW_PIPES 1
 #ifdef __clang__
 #if __has_extension(sycl_extended_atomics)