Should pass valid filter handle, not the netlink flags.

Fixes: 30a391a1 ("net sched filters: pass netlink message flags in event notification")
Signed-off-by: NRoman Mashak <mrv@mojatatu.com>
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Reported-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>