[DISC] make mi scale weighing_mode and unit enum (#1766)

* make mi scale weighing_mode and unit enum

* lint

main/config_mqttDiscovery.h

@@ -88,7 +88,7 @@ extern void createDiscovery(const char* sensor_type,
                             int off_delay,
                             const char* payload_available, const char* payload_not_available, bool gateway_entity, const char* command_topic,
                             const char* device_name, const char* device_manufacturer, const char* device_model, const char* device_mac, bool retainCmd,
-                            const char* state_class, const char* state_off = nullptr, const char* state_on = nullptr);
+                            const char* state_class, const char* state_off = nullptr, const char* state_on = nullptr, const char* enum_options = nullptr);
 
 /**
  * @brief Create a message for Discovery Device Trigger. For HA @see https://www.home-assistant.io/integrations/device_trigger.mqtt/
@@ -196,7 +196,8 @@ const char* availableHASSClasses[] = {"battery",
                                       "current",
                                       "energy",
                                       "power_factor",
-                                      "voltage"};
+                                      "voltage",
+                                      "enum"};
 
 // From https://github.com/home-assistant/core/blob/d7ac4bd65379e11461c7ce0893d3533d8d8b8cbf/homeassistant/const.py#L379
 // List of units available in Home Assistant