Fix ARM build.

src/platform-linux.cc

Index: src/platform-linux.cc
diff --git a/src/platform-linux.cc b/src/platform-linux.cc
index 6948653fedbfdce33e682b2f1d2fcb3a1aab38d0..46c74b017ff0181bd8b2b6ccedd5f51def079cd0 100644
--- a/src/platform-linux.cc
+++ b/src/platform-linux.cc
@@ -186,21 +186,10 @@ int OS::ActivationFrameAlignment() {
 }
 
 
-#ifdef V8_TARGET_ARCH_ARM
-// 0xffff0fa0 is the hard coded address of a function provided by
-// the kernel which implements a memory barrier. On older
-// ARM architecture revisions (pre-v6) this may be implemented using
-// a syscall. This address is stable, and in active use (hard coded)
-// by at least glibc-2.7 and the Android C library.
-typedef void (*LinuxKernelMemoryBarrierFunc)(void);
-LinuxKernelMemoryBarrierFunc pLinuxKernelMemoryBarrier __attribute__((weak)) =
-    (LinuxKernelMemoryBarrierFunc) 0xffff0fa0;
-#endif
-
 void OS::ReleaseStore(volatile AtomicWord* ptr, AtomicWord value) {
 #if defined(V8_TARGET_ARCH_ARM) && defined(__arm__)
   // Only use on ARM hardware.
-  pLinuxKernelMemoryBarrier();
+  MemoryBarrier();
 #else
   __asm__ __volatile__("" : : : "memory");
   // An x86 store acts as a release barrier.