don't suppose that string literals can be casted to non-const char *, newer compilers complain about it (replaces patch 974652)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@27952 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/intl.cpp

@@ -1575,6 +1575,9 @@ bool wxLocale::Init(int language, int flags)
         #define SETLOCALE_FAILS_ON_UNICODE_LANGS
     #endif
 
+#if !wxUSE_UNICODE
+    const
+#endif
     wxMB2WXbuf retloc = wxT("C");
     if (language != wxLANGUAGE_DEFAULT)
     {