message: refine comment explaining the order of checks on deallocate
diff: @@ -276,7 +276,7 @@ impl<'a, 'tcx> Memory<'a, 'tcx> {
  }
  {
  - // Some code somewhere seems to rely on us *not* removing the allocation when we yield this kind of error.
  + // deallocate_local in eval_context.rs relies on nothing actually having changed when this error occurs.
  // So we do this test in advance.
  let alloc = self.get(ptr.alloc_id)?;
  if alloc.static_kind != StaticKind::NotStatic {
  