Removes unused WaveOut APIs from ADM

webrtc/modules/audio_device/linux/audio_device_alsa_linux.h

Index: webrtc/modules/audio_device/linux/audio_device_alsa_linux.h
diff --git a/webrtc/modules/audio_device/linux/audio_device_alsa_linux.h b/webrtc/modules/audio_device/linux/audio_device_alsa_linux.h
index 7e07ed82d61c7410def0df27a882d6f762ea8a5f..f7fb9a90adbe9f72aa57982fc01c1e993c4e0c5d 100644
--- a/webrtc/modules/audio_device/linux/audio_device_alsa_linux.h
+++ b/webrtc/modules/audio_device/linux/audio_device_alsa_linux.h
@@ -83,12 +83,6 @@ public:
     int32_t SetAGC(bool enable) override;
     bool AGC() const override;
 
-    // Volume control based on the Windows Wave API (Windows only)
-    int32_t SetWaveOutVolume(uint16_t volumeLeft,
-                             uint16_t volumeRight) override;
-    int32_t WaveOutVolume(uint16_t& volumeLeft,
-                          uint16_t& volumeRight) const override;
-
     // Audio mixer initialization
     int32_t InitSpeaker() override;
     bool SpeakerIsInitialized() const override;