Use const more places

Change-Id: Ibc068d319d6fff26f2d11248e17481d8f7f027e0
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index ef90952..4028167 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -5207,7 +5207,7 @@
 
 void AudioFlinger::RecordThread::audioConfigChanged_l(int event, int param) {
     AudioSystem::OutputDescriptor desc;
-    void *param2 = NULL;
+    const void *param2 = NULL;
 
     switch (event) {
     case AudioSystem::INPUT_OPENED: