Fix memory corruption if increaseSamplingN is not called

Change-Id: Icbf9aaf68c25ba3330ceb79167bd776cf0342d0d
diff --git a/services/audioflinger/FastThreadState.cpp b/services/audioflinger/FastThreadState.cpp
index d4d6255..6994872 100644
--- a/services/audioflinger/FastThreadState.cpp
+++ b/services/audioflinger/FastThreadState.cpp
@@ -35,7 +35,7 @@
     /* mMeasuredWarmupTs({0, 0}), */
     mWarmupCycles(0)
 #ifdef FAST_MIXER_STATISTICS
-    , mSamplingN(0), mBounds(0)
+    , mSamplingN(1), mBounds(0)
 #endif
 {
     mMeasuredWarmupTs.tv_sec = 0;