Audio policy HAL set_ringer_mode is deprecated

Change-Id: If0f82d5c1cb9a0faf70f5a8434f68cdc39784ee6
diff --git a/include/hardware/audio_policy.h b/include/hardware/audio_policy.h
index 243f416..454ac85 100644
--- a/include/hardware/audio_policy.h
+++ b/include/hardware/audio_policy.h
@@ -101,7 +101,7 @@
      * by audio_mode_t */
     void (*set_phone_state)(struct audio_policy *pol, audio_mode_t state);
 
-    /* indicate a change in ringer mode */
+    /* deprecated, never called (was "indicate a change in ringer mode") */
     void (*set_ringer_mode)(struct audio_policy *pol, uint32_t mode,
                             uint32_t mask);
 
diff --git a/modules/audio/audio_policy.c b/modules/audio/audio_policy.c
index 06ac976..905c210 100644
--- a/modules/audio/audio_policy.c
+++ b/modules/audio/audio_policy.c
@@ -62,6 +62,7 @@
 {
 }
 
+// deprecated, never called
 static void ap_set_ringer_mode(struct audio_policy *pol, uint32_t mode,
                                uint32_t mask)
 {