Support AM/FM channel name in Russound RIO (home-assistant#148421)

Author: noahhusby

homeassistant/components/russound_rio/media_player.py

@@ -132,7 +132,7 @@ def source_list(self) -> list[str]:
     @property
     def media_title(self) -> str | None:
         """Title of current playing media."""
-        return self._source.song_name
+        return self._source.song_name or self._source.channel
 
     @property
     def media_artist(self) -> str | None: