MFC: r216691

MFC: r216691
Since VOP_READDIR() for ZFS does not return monotonically
increasing directory offset cookies, disable the UFS related
loop that skips over directory entries at the beginning of
the block for the experimental NFS server. This loop is
required for UFS since it always returns directory entries
starting at the beginning of the block that
the requested directory offset is in. In discussion with pjd@
and mckusick@ it seems that this behaviour of UFS should maybe
change, with this fix being an interim patch until then.
This patch only fixes the experimental server, since pjd@ is
working on a patch for the regular server.

git-svn-id: svn://svn.freebsd.org/base/stable/8@216786 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f