Update clang to r339409.

Change-Id: I800772d2d838223be1f6b40d490c4591b937fca2
diff --git a/linux-x64/clang/include/llvm/ADT/PackedVector.h b/linux-x64/clang/include/llvm/ADT/PackedVector.h
index 95adc29..3d53c49 100644
--- a/linux-x64/clang/include/llvm/ADT/PackedVector.h
+++ b/linux-x64/clang/include/llvm/ADT/PackedVector.h
@@ -65,7 +65,7 @@
   }
 };
 
-/// \brief Store a vector of values using a specific number of bits for each
+/// Store a vector of values using a specific number of bits for each
 /// value. Both signed and unsigned types can be used, e.g
 /// @code
 ///   PackedVector<signed, 2> vec;