[fs.class.directory.entry.general] Remove unneeded "unneeded"

per @Quuxplusone's suggestion

It is a bit tautological to say "unneeded call" in a note, because
implementations should always prevent unneeded calls.

Co-authored-by: Arthur O'Dwyer <[email protected]>

Author: frederick-vs-ja

source/iostreams.tex

@@ -16121,7 +16121,7 @@
 Friendship allows the \tcode{directory_iterator} implementation to cache
 already available attribute values
 directly into a \tcode{directory_entry} object
-without the cost of an unneeded call to \tcode{refresh()}.
+without the cost of a call to \tcode{refresh()}.
 \end{note}
 
 \pnum