Revert r240137 (Fixed/added namespace ending comments using clang-tidy. NFC)

Apparently, the style needs to be agreed upon first.

llvm-svn: 240390
diff --git a/llvm/lib/Support/FileOutputBuffer.cpp b/llvm/lib/Support/FileOutputBuffer.cpp
index 6f064c9..307ff09 100644
--- a/llvm/lib/Support/FileOutputBuffer.cpp
+++ b/llvm/lib/Support/FileOutputBuffer.cpp
@@ -109,4 +109,4 @@
   // Rename file to final name.
   return sys::fs::rename(Twine(TempPath), Twine(FinalPath));
 }
-} // namespace llvm
+} // namespace