Fix --disable-threads build, PR7949.

llvm-svn: 111676

llvm/lib/System/ThreadLocal.cpp

@@ -27,6 +27,7 @@ ThreadLocalImpl::ThreadLocalImpl() { }
 ThreadLocalImpl::~ThreadLocalImpl() { }
 void ThreadLocalImpl::setInstance(const void* d) { data = const_cast<void*>(d);}
 const void* ThreadLocalImpl::getInstance() { return data; }
+void ThreadLocalImpl::removeInstance() { data = 0; }
 }
 #else