vol: correct old conditional for IH_CONDSYNC

Two places in the vol package performed IH_CONDSYNC(vp->linkHandle)
only if AFS_NT40_ENV.  This was correct when the namei implementation
was windows only; however, this ifdef was apparently overlooked
when namei was implemented for UNIX.

Reviewed-on: http://gerrit.openafs.org/8815
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
(cherry picked from commit 19f424ecc26b02b210a3ba54b93846dddba14ede)

Change-Id: I944004d77ab17938465aa39f37d931df0adcd725
Reviewed-on: http://gerrit.openafs.org/9510
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Mark Vitale <mvitale@sinenomine.net>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>