afs: Clear VHardMount on ResetVolumeInfo

afs: Clear VHardMount on ResetVolumeInfo

afs_Analyze sets VHardMount on a volume struct when a hard-mount
scenario is encountered, and clears it after sleeping. However, if the
volume struct has VRecheck set, or if it's not in memory, afs_Analyze
cannot retrieve the volume struct in order to clear VHardMount again.

For the VRecheck case, this can results in VHardMount never getting
cleared, and so hard-mount messages for the volume seem to disappear.
So, clear VHardMount when we set VRecheck so this does not occur.

For the case where the volume struct is not in memory, this is not a
problem, since when we allocate a volume struct again, the VHardMount
state will not be retained.

Change-Id: I607741241e330391b8c857b2a72f0e0cfc0b91cc
Reviewed-on: http://gerrit.openafs.org/6335
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: BuildBot <buildbot@rampaginggeek.com>