[Flang][OpenMP] Fix to construct-names inside OpenMP construct with default(none) (llvm#82479)

When a do loop with a construct-name is used inside OpenMP construct
with default(none), an incorrect error will be raised as below.

```
program cn_and_default
    implicit none
    integer :: i

    !$omp parallel default(none)
        loop: do i = 1, 10
        end do loop
    !$omp end parallel
end program
```

> The DEFAULT(NONE) clause requires that 'loop' must be listed in a
data-sharing attribute clause

This patch fixes this by adding a condition to check and skip processing
construct-names.

Author: harishch4

flang/lib/Semantics/resolve-directives.cpp

@@ -1982,6 +1982,12 @@ void OmpAttributeVisitor::Post(const parser::OpenMPAllocatorsConstruct &x) {
 void OmpAttributeVisitor::Post(const parser::Name &name) {
   auto *symbol{name.symbol};
   if (symbol && !dirContext_.empty() && GetContext().withinConstruct) {
+    // Exclude construct-names
+    if (auto *details{symbol->detailsIf<semantics::MiscDetails>()}) {
+      if (details->kind() == semantics::MiscDetails::Kind::ConstructName) {
+        return;
+      }
+    }
     if (!symbol->owner().IsDerivedType() && !IsProcedure(*symbol) &&
         !IsObjectWithDSA(*symbol) && !IsNamedConstant(*symbol)) {
       // TODO: create a separate function to go through the rules for

flang/test/Semantics/OpenMP/default-none.f90

@@ -39,3 +39,11 @@ subroutine sb3(x)
    print *, x
  end subroutine
 end subroutine
+
+!construct-name inside default(none)
+subroutine sb4
+  !$omp parallel default(none)
+    loop: do i = 1, 10
+    end do loop
+  !$omp end parallel
+end subroutine