The user's mount options and the set of versions to try should not

change over the course of mount retries.

With this patch, each version-specific mount attempt is compartment-
alized, and starts from the user's original mount options each time.
Thus these attempts can now be safely performed in any order,
depending on what the user has requested, what the server advertises,
and what is up and running at any given point.

Don't regress the fix in commit 23c1a452.  For v2/v3 negotation, only
the user's mount options are written to /etc/mtab, and not any options
that were negotiated by mount.nfs.  There's no way to guarantee that
the server configuration will be the same at umount time as it was at
mount time.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steve Dickson <steved@redhat.com>