venus: make cacheout build again

venus: make cacheout build again

Make src/venus/cacheout buildable again, by fixing several compiler
errors and warnings. Also clean up a few small things, like adding
'static' qualifiers.

Change-Id: I1cd10221a5e13a59227e4915991db6042325b7de
Reviewed-on: http://gerrit.openafs.org/2605
Tested-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 4b7038820c503445917087ca4034ae48c7803518)
Reviewed-on: http://gerrit.openafs.org/2674