fix libstdc++/45990

[Jonathan Wakely]

This is Library Working Group issue 1337, which is still open but has
got five votes for Tentatively Ready on the lib reflector ... and it's
obviously right!

Tested x86_64-linux (and Solaris by Rainer) - committed to trunk.

	PR libstdc++/45990
	* include/bits/regex.h (regex_traits::isctype): DR 1337.


Index: include/bits/regex.h
===================================================================
--- include/bits/regex.h	(revision 165437)
+++ include/bits/regex.h	(working copy)
@@ -287,7 +287,7 @@ namespace std
       const ctype<_Ch_type>& __ctype(use_facet<
 				     ctype<_Ch_type> >(_M_locale));

-      if (__ctype.is(__c, __f))
+      if (__ctype.is(__f, __c))
 	return true;

       // special case of underscore in [[:w:]]