Fixed/added namespace ending comments using clang-tidy. NFC

The patch is generated using this command:

  $ tools/extra/clang-tidy/tool/run-clang-tidy.py -fix \
      -checks=-*,llvm-namespace-comment -header-filter='llvm/.*|clang/.*' \
      work/llvm/tools/clang

To reduce churn, not touching namespaces spanning less than 10 lines.

llvm-svn: 240270
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 0feeaa0..7ad2fec 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -293,8 +293,8 @@
     return Seq[Index];
   }
 };
-}
-}
+} // namespace yaml
+} // namespace llvm
 
 namespace clang {
 namespace format {