A64: Synchronize with r16356.

src/platform-posix.cc

Index: src/platform-posix.cc
diff --git a/src/platform-posix.cc b/src/platform-posix.cc
index 07269a236926f5e47b7e317d0fdeeea4d4db5fb2..acef4f9c306674b16a621b019e18f8ee862f3f52 100644
--- a/src/platform-posix.cc
+++ b/src/platform-posix.cc
@@ -79,11 +79,11 @@ static const pthread_t kNoThread = (pthread_t) 0;
 
 
 uint64_t OS::CpuFeaturesImpliedByPlatform() {
-#if defined(__APPLE__)
+#if V8_OS_MACOSX
   // Mac OS X requires all these to install so we can assume they are present.
   // These constants are defined by the CPUid instructions.
   const uint64_t one = 1;
-  return (one << SSE2) | (one << CMOV) | (one << RDTSC) | (one << CPUID);
+  return (one << SSE2) | (one << CMOV);
 #else
   return 0;  // Nothing special about the other systems.
 #endif