Fix build warnings

Change-Id: Ife5e40264f43fb3ccb40830228701003fe106bf5
diff --git a/services/audioflinger/tests/resampler_tests.cpp b/services/audioflinger/tests/resampler_tests.cpp
index 169ce02..d6217ba 100644
--- a/services/audioflinger/tests/resampler_tests.cpp
+++ b/services/audioflinger/tests/resampler_tests.cpp
@@ -60,7 +60,7 @@
         int check = memcmp((const char*)reference + i * outputFrameSize,
                 (const char*)test + i * outputFrameSize, outputFrameSize);
         if (check) {
-            ALOGE("Failure at frame %d", i);
+            ALOGE("Failure at frame %zu", i);
             ASSERT_EQ(check, 0); /* fails */
         }
     }