smack: Remove IPPROTO_UDPLITE support in security_sock_rcv_skb().

smack: Remove IPPROTO_UDPLITE support in security_sock_rcv_skb().

smack_socket_sock_rcv_skb() is registered as socket_sock_rcv_skb,
which is called as security_sock_rcv_skb() in sk_filter_trim_cap().

Now that UDP-Lite is gone, let's remove the IPPROTO_UDPLITE support
in smack_socket_sock_rcv_skb().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Link: https://patch.msgid.link/20260311052020.1213705-7-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>