Same fix for non-constant string.

The playlist works fine again (with ASCII/Latin locale charset).
When in UTF8, it might be a good idea to check for invalid bytes
sequences and replace them with question mark - at the moment
wxWidgets still leave the whole text blank which result in blank
playlist item in the playlist.

modules/gui/wxwindows/wxwindows.h

@@ -69,7 +69,7 @@ DECLARE_LOCAL_EVENT_TYPE( wxEVT_INTF, 1 );
 #if wxUSE_UNICODE
 #   define wxU(ansi) wxString(ansi, wxConvLocal)
 #else
-#   define wxU(ansi) ansi
+#   define wxU(ansi) (ansi)
 #endif
 #define ISUTF8 0
 
@@ -77,11 +77,7 @@ DECLARE_LOCAL_EVENT_TYPE( wxEVT_INTF, 1 );
 
 /* wxL2U (locale to unicode) is used to convert ansi strings to unicode
  * strings (wchar_t) */
-#if wxUSE_UNICODE
-#   define wxL2U(ansi) wxString(ansi, *wxConvCurrent)
-#else
-#   define wxL2U(ansi) ansi
-#endif
+#define wxL2U(ansi) wxU(ansi)
 
 #define WRAPCOUNT 80