[TableGen] Correct comments for end of namespace. NFC

Summary:
Update end-of-namespace comments generated by
tablegen emitters to fulfill the rules setup by
clang-tidy's llvm-namespace-comment checker.

Fixed a few end-of-namespace comments in the
tablegen source code as well.

Reviewers: craig.topper

Reviewed By: craig.topper

Subscribers: craig.topper, stoklund, dschuff, sbc100, jgravelle-google, aheejin, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66396

llvm-svn: 369865
diff --git a/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp b/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp
index dc9dfa8f..01f4115 100644
--- a/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp
+++ b/llvm/utils/TableGen/FixedLenDecoderEmitter.cpp
@@ -2465,7 +2465,7 @@
   // Emit the main entry point for the decoder, decodeInstruction().
   emitDecodeInstruction(OS);
 
-  OS << "\n} // End llvm namespace\n";
+  OS << "\n} // end namespace llvm\n";
 }
 
 namespace llvm {