add wildcard branches for matches on enums

src/codec/audio_service.rs

@@ -27,6 +27,8 @@ impl From<AVAudioServiceType> for AudioService {
             AV_AUDIO_SERVICE_TYPE_VOICE_OVER => AudioService::VoiceOver,
             AV_AUDIO_SERVICE_TYPE_KARAOKE => AudioService::Karaoke,
             AV_AUDIO_SERVICE_TYPE_NB => AudioService::Main,
+
+            _ => unimplemented!(),
         }
     }
 }