Move local variable declarations to point of first use

Change-Id: Ideb83dea2c3002651c34fa646753cba598e29e93
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index f27d908..4bcc058 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -3294,11 +3294,11 @@
 
 void AudioFlinger::DirectOutputThread::threadLoop_mix()
 {
-    AudioBufferProvider::Buffer buffer;
     size_t frameCount = mFrameCount;
     int8_t *curBuf = (int8_t *)mMixBuffer;
     // output audio to hardware
     while (frameCount) {
+        AudioBufferProvider::Buffer buffer;
         buffer.frameCount = frameCount;
         mActiveTrack->getNextBuffer(&buffer);
         if (CC_UNLIKELY(buffer.raw == NULL)) {