[AUDIT] Avoid using %*.*s format strings.

They don't seem to work correctly (investigation ongoing), but we don't
actually need to do it anyway.

Patch from Peter Martuccelli <peterm@redhat.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

[AUDIT] Fix signedness of 'serial' in various routines.

Attached is a patch that corrects a signed/unsigned warning. I also noticed
that we needlessly init serial to 0. That only needs to occur if the kernel
was compiled without the audit system.

-Steve Grubb

Signed-off-by: David Woodhouse <dwmw2@infradead.org>