Re-enable WebRtcIsacfix_AllpassFilter2FixDec16Neon

webrtc/modules/audio_coding/codecs/isac/fix/source/isacfix.c

Index: webrtc/modules/audio_coding/codecs/isac/fix/source/isacfix.c
diff --git a/webrtc/modules/audio_coding/codecs/isac/fix/source/isacfix.c b/webrtc/modules/audio_coding/codecs/isac/fix/source/isacfix.c
index 43a9e521277f347775c1e3739f2ed6e5ea0ec669..ba055ebdf53c9fcab9f2e1f3c80ad5c0c4794f28 100644
--- a/webrtc/modules/audio_coding/codecs/isac/fix/source/isacfix.c
+++ b/webrtc/modules/audio_coding/codecs/isac/fix/source/isacfix.c
@@ -207,13 +207,8 @@ static void WebRtcIsacfix_InitNeon(void) {
   WebRtcIsacfix_FilterMaLoopFix = WebRtcIsacfix_FilterMaLoopNeon;
   WebRtcIsacfix_Spec2Time = WebRtcIsacfix_Spec2TimeNeon;
   WebRtcIsacfix_Time2Spec = WebRtcIsacfix_Time2SpecNeon;
-// Disable AllpassFilter2FixDec16Neon function due to a clang bug.
-// Refer more details at:
-// https://code.google.com/p/webrtc/issues/detail?id=4567
-#if !defined(__clang__) || !defined(WEBRTC_ARCH_ARM64)
   WebRtcIsacfix_AllpassFilter2FixDec16 =
       WebRtcIsacfix_AllpassFilter2FixDec16Neon;
-#endif
   WebRtcIsacfix_MatrixProduct1 = WebRtcIsacfix_MatrixProduct1Neon;
   WebRtcIsacfix_MatrixProduct2 = WebRtcIsacfix_MatrixProduct2Neon;
 }