Make the deprecation notice use the same form as other such notices.

This has sat around in a deprecated state for a *long* time!

Doc/lib/libposixfile.tex

@@ -11,9 +11,9 @@
 
 \indexii{\POSIX{}}{file object}
 
-\note{This module will become obsolete in a future release.
-The locking operation that it provides is done better and more
-portably by the \function{fcntl.lockf()} call.%
+\deprecated{1.5}{The locking operation that this module provides is
+done better and more portably by the
+\function{\refmodule{fcntl}.lockf()} call.
 \withsubitem{(in module fcntl)}{\ttindex{lockf()}}}
 
 This module implements some additional functionality over the built-in