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/AArch64/MCTargetDesc/AArch64MachObjectWriter.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MachObjectWriter.cpp
index 741b273..b2f5bf3 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MachObjectWriter.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64MachObjectWriter.cpp
@@ -38,7 +38,7 @@
                         const MCFixup &Fixup, MCValue Target,
                         uint64_t &FixedValue) override;
 };
-}
+} // namespace
 
 bool AArch64MachObjectWriter::getAArch64FixupKindMachOInfo(
     const MCFixup &Fixup, unsigned &RelocType, const MCSymbolRefExpr *Sym,