Migrate xbee light to ColorMode (#70907)

homeassistant/components/xbee/light.py

@@ -3,7 +3,7 @@ from __future__ import annotations
 
 import voluptuous as vol
 
-from homeassistant.components.light import LightEntity
+from homeassistant.components.light import ColorMode, LightEntity
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
 from homeassistant.helpers.typing import ConfigType, DiscoveryInfoType
@@ -29,3 +29,6 @@ def setup_platform(
 
 class XBeeLight(XBeeDigitalOut, LightEntity):
     """Use XBeeDigitalOut as light."""
+
+    _attr_color_mode = ColorMode.ONOFF
+    _attr_supported_color_modes = {ColorMode.ONOFF}