afs: Fix VLRU traversal sanity check

afs: Fix VLRU traversal sanity check

On non-Linux, the number of vcaches in the VLRU can easily exceed
afs_maxvcount, since we allocate new vcaches when we run out. So,
assume we only have afs_vcount vcaches on the VLRU, instead of
assuming we have at most afs_maxvcount vcaches.

Reviewed-on: http://gerrit.openafs.org/8471
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
(cherry picked from commit bc6dd95016c63d0742698d902aebf73c01162c24)

Change-Id: Id4884e45a52813eb33926958b11148a021ca3057
Reviewed-on: http://gerrit.openafs.org/8606
Reviewed-by: Michael Meffie <mmeffie@sinenomine.net>
Reviewed-by: Paul Smeddle <paul.smeddle@gmail.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Stephan Wiesand <stephan.wiesand@desy.de>
Tested-by: Stephan Wiesand <stephan.wiesand@desy.de>