Fix Solaris V8 build

Patch submitted to V8: http://codereview.chromium.org/2282003/show

deps/v8/src/platform-solaris.cc

@@ -107,6 +107,12 @@ int OS::ActivationFrameAlignment() {
 }
 
 
+void OS::ReleaseStore(volatile AtomicWord* ptr, AtomicWord value) {
+  __asm__ __volatile__("" : : : "memory");
+  *ptr = value;
+}
+
+
 const char* OS::LocalTimezone(double time) {
   if (isnan(time)) return "";
   time_t tv = static_cast<time_t>(floor(time/msPerSecond));