[fs.class.directory.iterator.general] Don't mention friendship

Author: frederick-vs-ja

source/iostreams.tex

@@ -16384,8 +16384,6 @@
 any \tcode{directory_entry} \tcode{refresh} function.
 \begin{note}
 The exact mechanism for storing cached attribute values is not exposed to users.
-For exposition, class \tcode{directory_iterator} is shown in \ref{fs.class.directory.entry}
-as a friend of class \tcode{directory_entry}.
 \end{note}
 
 \pnum