afsd: look in the right place for -splitcache argument

afsd: look in the right place for -splitcache argument

The argument to -splitcache is in as->parms[34], not [30].

Found-by: clang static analyzer
Reviewed-on: http://gerrit.openafs.org/5169
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Simon Wilkinson <sxw@inf.ed.ac.uk>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 90ea68979c6740583747d0af500ed4a034eba651)

Change-Id: Iff8072cf8c7b5d9a5d7486fc9778f079fab1426c
Reviewed-on: http://gerrit.openafs.org/5223
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>