Use AFS_PTR_FMT to format pointers

Use AFS_PTR_FMT to format pointers

Replace "0x%x" with "%"AFS_FMT_PTR for pointer printing in all locations
where gcc flags a warning.

This change is warnings reduction driven - there are many more
occurences of this in the code which don't currently result in
compiler warnings, because the va_args functions they're used in
aren't defined as printflike.

Reviewed-on: http://gerrit.openafs.org/75
Verified-by: Russ Allbery <rra@stanford.edu>
Reviewed-by: Russ Allbery <rra@stanford.edu>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Verified-by: Jeffrey Altman <jaltman@openafs.org>
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>