[llvm] Add missing include for !LLVM_ENABLE_THREADS

thread.h used report_fatal_error without including ErrorHandling.h

Author: Bigcheese

llvm/include/llvm/Support/thread.h

@@ -213,6 +213,7 @@ inline thread::id get_id() { return std::this_thread::get_id(); }
 
 #else // !LLVM_ENABLE_THREADS
 
+#include "llvm/Support/ErrorHandling.h"
 #include <utility>
 
 namespace llvm {