[DFT] Use matching styles for a preprocessor macro

Author: rafbiels

src/dft/execute_helper_generic.hpp

@@ -39,7 +39,7 @@ namespace oneapi::math::dft::detail {
  */
 template <typename HandlerT, typename FnT>
 static inline void fft_enqueue_task(HandlerT&& cgh, FnT&& f) {
-#ifdef __ADAPTIVECPP__
+#if defined(__ADAPTIVECPP__)
     cgh.AdaptiveCpp_enqueue_custom_operation([=](sycl::interop_handle ih) {
 #elif defined(SYCL_EXT_ONEAPI_ENQUEUE_NATIVE_COMMAND)
     cgh.ext_codeplay_enqueue_native_command([=](sycl::interop_handle ih) {