sysfs: cleanup: add missing namespace comment

Namespace was missing terminator comment.

Change-Id: I9a35742fbdf5c0cdf162dfead0e86864b635a9ab
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/sysfs.hpp b/sysfs.hpp
index 86be6da..f66c3fb 100644
--- a/sysfs.hpp
+++ b/sysfs.hpp
@@ -167,6 +167,6 @@
         std::string p;
 };
 } // namespace hwmonio
-}
+} // namespace sysfs
 
 // vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4