review: add liscence

Author: inbelic

clang/lib/Parse/ParseHLSLRootSignature.cpp

@@ -1,3 +1,11 @@
+//=== ParseHLSLRootSignature.cpp - Parse Root Signature -------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
 #include "clang/Parse/ParseHLSLRootSignature.h"
 
 #include "clang/Lex/LiteralSupport.h"