[TableGen] Fix comments/headers referencing clang (NFC)

Remove references to clang's TableGen implementation. Presumably these
files were originally copied over.

llvm-svn: 366982
diff --git a/lldb/utils/TableGen/LLDBOptionDefEmitter.cpp b/lldb/utils/TableGen/LLDBOptionDefEmitter.cpp
index 74e420e..537f71c 100644
--- a/lldb/utils/TableGen/LLDBOptionDefEmitter.cpp
+++ b/lldb/utils/TableGen/LLDBOptionDefEmitter.cpp
@@ -1,4 +1,4 @@
-//===- TableGen.cpp - Top-Level TableGen implementation for Clang ---------===//
+//===- LLDBOptionDefEmitter.cpp -------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.