Use audio_in_acoustics_t consistently

Change-Id: I0a9dd668fb2e57b1c3ece3190588194974b99062
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index 766ba44..ca65ecb 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -131,7 +131,7 @@
                             uint32_t *pSamplingRate,
                             audio_format_t *pFormat,
                             uint32_t *pChannels,
-                            uint32_t acoustics);
+                            audio_in_acoustics_t acoustics);
 
     virtual status_t closeInput(int input);