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

The patch is generated using this command:

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


Thanks to Eugene Kosov for the original patch!

llvm-svn: 240137
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
index 804d353..9fe27fb 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
@@ -40,7 +40,7 @@
     bool needsRelocateWithSymbol(const MCSymbol &Sym,
                                  unsigned Type) const override;
   };
-}
+} // namespace
 
 ARMELFObjectWriter::ARMELFObjectWriter(uint8_t OSABI)
   : MCELFObjectTargetWriter(/*Is64Bit*/ false, OSABI,