Remove incorrect comment

The negative concept is required for subsumption to work, it's not a
bug.

	* include/bits/iterator_concepts.h (__iter_without_nested_types):
	Remove incorrect comment.

From-SVN: r277848

libstdc++-v3/ChangeLog

+2019-11-05  Jonathan Wakely  <jwakely@redhat.com>
+
+	* include/bits/iterator_concepts.h (__iter_without_nested_types):
+	Remove incorrect comment.
+
 2019-10-31  Jonathan Wakely  <jwakely@redhat.com>
 
 	* doc/html/*: Regenerate.

libstdc++-v3/include/bits/iterator_concepts.h

@@ -309,7 +309,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	typename _Iter::reference;
       };
 
-    // FIXME: needed due to PR c++/92102
     template<typename _Iter>
       concept __iter_without_nested_types = !__iter_with_nested_types<_Iter>;