new loplugin:returnconstant

look for methods that always return the same value

Change-Id: I5f1c5b58a985ecf5f7765a2d4ebd464eae5ef76f
Reviewed-on: https://gerrit.libreoffice.org/57973
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

compilerplugins/clang/pluginhandler.cxx

@@ -49,7 +49,7 @@ struct PluginData
     bool byDefault;
 };
 
-const int MAX_PLUGINS = 100;
+const int MAX_PLUGINS = 200;
 static PluginData plugins[ MAX_PLUGINS ];
 static int pluginCount = 0;
 static bool bPluginObjectsCreated = false;