audio: Add support for voice session mic mute

Change-Id: I5277736fffcb4511e4a7adb2e3e10090dcab484c
diff --git a/audio/voice.h b/audio/voice.h
index 352e839..10f0fef 100644
--- a/audio/voice.h
+++ b/audio/voice.h
@@ -39,6 +39,7 @@
 void stop_voice_session(struct voice_session *session);
 void set_voice_session_volume(struct voice_session *session, float volume);
 void set_voice_session_audio_path(struct voice_session *session);
+void set_voice_session_mic_mute(struct voice_session *session, bool state);
 
 bool voice_session_uses_twomic(struct voice_session *session);
 bool voice_session_uses_wideband(struct voice_session *session);