selinux: Cleanup printk logging in policydb

Replace printk with pr_* to avoid checkpatch warnings and
replace KERN_CONT with 2 longer prints.

Signed-off-by: Peter Enderborg <peter.enderborg@sony.com>
[PM: fixed some missing newlines identified by Joe Perches]
Signed-off-by: Paul Moore <paul@paul-moore.com>