Fix unused parameter warnings in audio

Change-Id: I665ba3358dd9502f0adec70d486e7bf8a2e1b0fe
diff --git a/media/mediaserver/main_mediaserver.cpp b/media/mediaserver/main_mediaserver.cpp
index d5207d5..a347951 100644
--- a/media/mediaserver/main_mediaserver.cpp
+++ b/media/mediaserver/main_mediaserver.cpp
@@ -37,7 +37,7 @@
 
 using namespace android;
 
-int main(int argc, char** argv)
+int main(int argc __unused, char** argv)
 {
     signal(SIGPIPE, SIG_IGN);
     char value[PROPERTY_VALUE_MAX];