fixed passing raw unconverted strings through wxArgNormalizer<> for VC++

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@45795 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/strvararg.h

@@ -121,9 +121,9 @@ struct wxArgNormalizer
     // Returns the value in a form that can be safely passed to real vararg
     // functions. In case of strings, this is char* in ANSI build and wchar_t*
     // in Unicode build.
-    const T& get() const { return m_value; }
+    T get() const { return m_value; }
 
-    const T& m_value;
+    T m_value;
 };
 
 // normalizer for passing arguments to functions working with wchar_t* (and