Fix volatile type handling in openmp target data mappings

Author: ashermancinelli

flang/lib/Lower/ConvertExprToHLFIR.cpp

@@ -465,7 +465,10 @@ class HlfirDesignatorBuilder {
     // hlfir.designate result will be a pointer/allocatable.
     PartInfo partInfo;
     mlir::Type componentType = visitComponentImpl(component, partInfo).second;
-    mlir::Type designatorType = fir::ReferenceType::get(componentType);
+    const auto isVolatile =
+        fir::isa_volatile_type(partInfo.base.value().getBase().getType());
+    mlir::Type designatorType =
+        fir::ReferenceType::get(componentType, isVolatile);
     fir::FortranVariableFlagsAttr attributes =
         Fortran::lower::translateSymbolAttributes(getBuilder().getContext(),
                                                   component.GetLastSymbol());