budb: Add printf format checks to logging fns

budb: Add printf format checks to logging fns

Add format checking to the Log, LogError and LogDebug functions.

Fix the resulting type errors. One of these in particular is a
signficant bug, where we would try to print a hash table pointer
as a string.

Change-Id: I02d7bcd7ce63583d24dda4da40288af51a516583
Reviewed-on: http://gerrit.openafs.org/2445
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>