FBSD: warning cleanups

FBSD: warning cleanups

Only declare 'p' if it will be used; other unused variables;
signedness mismatches.

Kill spl with fire.

Reviewed-on: http://gerrit.openafs.org/3200
Tested-by: BuildBot <buildbot@rampaginggeek.com>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit ebd18bfade80bd66422aad4310375ee460cd1ed5)

Change-Id: Iac808cf603043a8996f1c8657765ef8a0a7e6d88
Change-Id: I163a4314a0598eec9a514bbc564d8dc2ff91acae
Reviewed-on: http://gerrit.openafs.org/3458
Tested-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Derrick Brashear <shadow@dementia.org>