lib: Add default config fallback for configured namespace

All settings in the configured global namespace fall back to libstrongswan.

src/libstrongswan/library.c

@@ -293,6 +293,9 @@ bool library_init(char *settings, const char *namespace)
 	this->objects = hashtable_create((hashtable_hash_t)hash,
 									 (hashtable_equals_t)equals, 4);
 	this->public.settings = settings_create(settings);
+	/* all namespace settings may fall back to libstrongswan */
+	lib->settings->add_fallback(lib->settings, lib->ns, "libstrongswan");
+
 	this->public.hosts = host_resolver_create();
 	this->public.proposal = proposal_keywords_create();
 	this->public.caps = capabilities_create();