vol, volser, and viced type fixes

vol, volser, and viced type fixes

Correct many uses of incorrect types for file offsets, sizes, etc. in
the volume server, fileserver, and the volume package.

Thanks to Tom Keiser who pointed out the incorrect types and suggested
solutions.

Change-Id: If4aedfe0cc06d05b3775069ae1285d4c330976cd
Reviewed-on: http://gerrit.openafs.org/1920
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Russ Allbery <rra@stanford.edu>