[flang] do concurrent: Enable delayed localization by default (#154303)

Enables delayed localization by default for `do concurrent`. Tested both
gfortran and Fujitsu test suites.

All tests pass for gfortran tests. For Fujitsu, enabled delayed
localization passes more tests:

Delayed localization disabled:
Testing Time: 7251.76s
  Passed            : 88520
  Failed            :   162
  Executable Missing:   408

Delayed localization enabled:
Testing Time: 7216.73s
  Passed            : 88522
  Failed            :   160
  Executable Missing:   408

Author: ergawy

flang/lib/Lower/Bridge.cpp

@@ -2064,8 +2064,7 @@ class FirConverter : public Fortran::lower::AbstractConverter {
     // TODO Promote to using `enableDelayedPrivatization` (which is enabled by
     // default unlike the staging flag) once the implementation of this is more
     // complete.
-    bool useDelayedPriv =
-        enableDelayedPrivatizationStaging && doConcurrentLoopOp;
+    bool useDelayedPriv = enableDelayedPrivatization && doConcurrentLoopOp;
     llvm::SetVector<const Fortran::semantics::Symbol *> allPrivatizedSymbols;
     llvm::SmallSet<const Fortran::semantics::Symbol *, 16> mightHaveReadHostSym;