vol: avoid -Wformat-truncation issues in vol-salvage.c

vol: avoid -Wformat-truncation issues in vol-salvage.c

Make some formerly-64-character buffers VMAXPATHLEN (plus a smidgeon)
to give them space to hold the composed paths.

Reviewed-on: https://gerrit.openafs.org/13464
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Cheyenne Wills <cwills@sinenomine.net>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Reviewed-by: Benjamin Kaduk <kaduk@mit.edu>
(cherry picked from commit d6b88e3bd5219a8dffebc07df23e30f1d16f095f)

Change-Id: Idd388cd23ffeff1307b9eb6d31976383b6125260
Reviewed-on: https://gerrit.openafs.org/13733
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Marcio Brito Barbosa <mbarbosa@sinenomine.net>
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>