Fix build warnings

Change-Id: I9e3cfa0c6b3467fe763ce55f759d179f02c5deea
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index d2b2931..a50c936 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -4217,7 +4217,7 @@
                 if (status == BAD_VALUE &&
                     reqFormat == mInput->stream->common.get_format(&mInput->stream->common) &&
                     reqFormat == AUDIO_FORMAT_PCM_16_BIT &&
-                    ((int)mInput->stream->common.get_sample_rate(&mInput->stream->common)
+                    (mInput->stream->common.get_sample_rate(&mInput->stream->common)
                             <= (2 * reqSamplingRate)) &&
                     popcount(mInput->stream->common.get_channels(&mInput->stream->common))
                             <= FCC_2 &&