gcc 4.0 compile fix by Arwed von Merkatz

modules/gui/wxwindows/playlist.cpp

@@ -52,6 +52,7 @@
 #define HELP_LOOP N_( "Repeat All" )
 #define HELP_REPEAT N_( "Repeat One" )
 
+namespace wxvlc {
 /* Callback prototype */
 static int PlaylistChanged( vlc_object_t *, const char *,
                             vlc_value_t, vlc_value_t, void * );
@@ -1517,3 +1518,4 @@ static int ItemAppended( vlc_object_t *p_this, const char *psz_variable,
 
     return VLC_SUCCESS;
 }
+}