volser: Fix a couple of assigned but not read errors

Fix a couple more errors where we assign to a variable, but never
read the result back out.

Caught by clang-analyzer

Change-Id: I78f8f1403d166c4231b0abdb607de77e9ed62a27
Reviewed-on: http://gerrit.openafs.org/9201
Reviewed-by: Derrick Brashear <shadow@your-file-system.com>
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Jeffrey Altman <jaltman@your-file-system.com>