Make volscan's column delimiter option work

Currently, volscan ignores the -delim command-line option,
using the hardcoded default. This patch adds processing
for this option, allowing alternative characters.

Corrects an error in a08c3207255756c825ab69a19e04f79dd879c646

Reviewed-on: http://gerrit.openafs.org/6894
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@secure-endpoints.com>
Tested-by: Jeffrey Altman <jaltman@secure-endpoints.com>
(cherry picked from commit d62456255e13beef41770ad90ee6cb58068007b9)

Change-Id: Ic5e253c2c1ae6fcdba79b70bf43ba16883389ccd
Reviewed-on: http://gerrit.openafs.org/11271
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>