SELinux: clean up printks

Make sure all printk start with KERN_*
Make sure all printk end with \n
Make sure all printk have the word 'selinux' in them
Change "function name" to "%s", __func__ (found 2 wrong)

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>