Audit: move audit_get_nd completely into audit_watch

audit_get_nd() is only used  by audit_watch and could be more cleanly
implemented by having the audit watch functions call it when needed rather
than making the generic audit rule parsing code deal with those objects.

Signed-off-by: Eric Paris <eparis@redhat.com>

diff --cc kernel/audit.h
Simple merge

diff --cc kernel/audit_watch.c
Simple merge

diff --cc kernel/auditfilter.c
Simple merge