[flang] Avoid new spurious error under -fopenacc (#78504)

Don't create HostAssocDetails symbols for subprograms in OpenACC
regions; it can cause warnings to became errors later in compilation
when calls do not appear to be to external procedures with implicit
interfaces.

flang/lib/Semantics/resolve-directives.cpp

@@ -1313,7 +1313,7 @@ void AccAttributeVisitor::Post(const parser::Name &name) {
   auto *symbol{name.symbol};
   if (symbol && !dirContext_.empty() && GetContext().withinConstruct) {
     if (!symbol->owner().IsDerivedType() && !symbol->has<ProcEntityDetails>() &&
-        !IsObjectWithDSA(*symbol)) {
+        !symbol->has<SubprogramDetails>() && !IsObjectWithDSA(*symbol)) {
       if (Symbol * found{currScope().FindSymbol(name.source)}) {
         if (symbol != found) {
           name.symbol = found; // adjust the symbol within region