Add missing file

Author: lbushi25

sycl/include/sycl/ext/oneapi/experimental/work_group_memory_forward_decl.hpp

@@ -0,0 +1,14 @@
+#pragma once
+#include <sycl/ext/oneapi/properties/properties.hpp>
+namespace sycl {
+inline namespace _V1 {
+namespace ext {
+namespace oneapi {
+namespace experimental {
+template <typename DataT, typename PropertiesT = empty_properties_t>
+class work_group_memory;
+} // namespace experimental
+} // namespace oneapi
+} // namespace ext
+} // namespace _V1
+} // namespace sycl