Patch from "Theodore Ts'o" <tytso@mit.edu>

The following patch should (in theory) fix the htree/NFS readdir problems
that people have reported.  Specifically, it should fix the NFS looping on
EOF problem with readdir, as well as the problems caused by coverting a
directory to HTREE while an NFS readdir is in progress problem.

I'd appreciate it if people who can easily replicate these NFS/htree problems
could give this patch (against BK-recent / 2.5.63) a whirl.  Thanks!!