charon-systemd: Inherit all settings from the charon section

Our default config files are very charon specific.  So to avoid
confusion when only charon-systemd is installed we just default to all
settings defined for charon.  Since charon-systemd probably won't be used
together with charon this should not cause conflicts (settings may still
be overridden via the charon-systemd section).

src/charon-systemd/charon-systemd.c

@@ -324,6 +324,15 @@ static plugin_feature_t features[] = {
 		PLUGIN_PROVIDE(CUSTOM, "systemd-journal"),
 };
 
+/**
+ * Add namespace alias
+ */
+static void __attribute__ ((constructor))register_namespace()
+{
+	/* inherit settings from charon */
+	library_add_namespace("charon");
+}
+
 /**
  * Main function, starts the daemon.
  */