Add precipitation device class (#14232)

src/common/const.ts

@@ -60,6 +60,7 @@ import {
   mdiWaterPercent,
   mdiWeatherCloudy,
   mdiWeatherPouring,
+  mdiWeatherRainy,
   mdiWeatherWindy,
   mdiWeight,
   mdiWhiteBalanceSunny,
@@ -147,6 +148,7 @@ export const FIXED_DEVICE_CLASS_ICONS = {
   pm25: mdiMolecule,
   power: mdiFlash,
   power_factor: mdiAngleAcute,
+  precipitation: mdiWeatherRainy,
   precipitation_intensity: mdiWeatherPouring,
   pressure: mdiGauge,
   reactive_power: mdiFlash,