replace rather than append to SUIL_MODULE_DIR

should fix http://tracker.ardour.org/view.php?id=5679

Author: x42

gtk2_ardour/main.cc

@@ -172,9 +172,9 @@ fixup_bundle_environment (int, char* [])
 	export_search_path (bundle_dir, "ARDOUR_INSTANT_XML_PATH", "/Resources");
 	export_search_path (bundle_dir, "LADSPA_PATH", "/Plugins");
 	export_search_path (bundle_dir, "VAMP_PATH", "/lib");
-	export_search_path (bundle_dir, "SUIL_MODULE_DIR", "/lib");
 	export_search_path (bundle_dir, "GTK_PATH", "/lib/gtkengines");
 
+	setenv ("SUIL_MODULE_DIR", (bundle_dir + "/lib").c_str(), 1);
 	setenv ("PATH", (bundle_dir + "/MacOS:" + std::string(getenv ("PATH"))).c_str(), 1);
 
 	/* unset GTK_RC_FILES so that we only load the RC files that we define
@@ -282,9 +282,9 @@ fixup_bundle_environment (int /*argc*/, char* argv[])
 	export_search_path (dir_path, "ARDOUR_DATA_PATH", "/share");
 	export_search_path (dir_path, "LADSPA_PATH", "/plugins");
 	export_search_path (dir_path, "VAMP_PATH", "/lib");
-	export_search_path (dir_path, "SUIL_MODULE_DIR", "/lib");
 	export_search_path (dir_path, "GTK_PATH", "/lib/gtkengines");
 
+	setenv ("SUIL_MODULE_DIR", (dir_path + "/lib").c_str(), 1);
 	setenv ("PATH", (dir_path + "/bin:" + std::string(getenv ("PATH"))).c_str(), 1);
 
 	/* unset GTK_RC_FILES so that we only load the RC files that we define