D-Bus (old): Fix wpsReg error message

This was supposed to return WpsRegError, not WpsPbcError.

Signed-off-by: Jouni Malinen <j@w1.fi>

wpa_supplicant/dbus/dbus_old_handlers_wps.c

@@ -144,7 +144,7 @@ DBusMessage * wpas_dbus_iface_wps_reg(DBusMessage *message,
 
 	if (ret < 0) {
 		return dbus_message_new_error(message,
-					      WPAS_ERROR_WPS_PBC_ERROR,
+					      WPAS_ERROR_WPS_REG_ERROR,
 					      "Could not request credentials");
 	}