DAFS: VRS_r with VOL_SALVAGE_NO_OFFLINE in attach2

One caller of VRequestSalvage_r in attach2 was not passing the
VOL_SALVAGE_NO_OFFLINE flag. This really should be passed for every
place that manually sets vp->nUsers = 0, since then the VPutVolume_r
handlers will never fire.

Reviewed-on: http://gerrit.openafs.org/8203
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
(cherry picked from commit 3237543afafae7191635fd8e8cada1f95e8abcff)

Change-Id: I44a9a56b849bc3c1473b290961190a47ad45f5b5
Reviewed-on: http://gerrit.openafs.org/9283
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>
Reviewed-by: Mark Vitale <mvitale@sinenomine.net>
Tested-by: BuildBot <buildbot@rampaginggeek.com>