orangefs: do not wait for timeout if umounting

[ Upstream commit b5a9d61eebdd0016ccb383b25a5c3d04977a6549 ]

When the computer is turned off, all the processes are killed and then
all the filesystems are umounted.  OrangeFS should not wait for the
userspace daemon to come back in that case.

This only works for plain umount(2).  To actually take advantage of this
interactively, `umount -f' is needed; otherwise umount will issue a
statfs first, which will wait for the userspace daemon to come back.

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>