Reject the unsupported and invalid ct_state flags of cls flower rules.

Fixes: e0ace68a ("net/sched: cls_flower: Add matching on conntrack info")
Signed-off-by: wenxu <wenxu@ucloud.cn>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>