RDMA/hns: Add support for sending port down event fastly

driver inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5Z2DS



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When the netdev port status changes, the roce driver sends a port down
event by parsing the netdev event dispatched by IB_CORE, which takes about
a few hundred milliseconds.
But,it is not fast enough for ULP sometimes.

The HNS NIC driver can directly notify the ROCE driver send port
event via callback function, this takes only a few milliseconds.
This patch implements this callback function.

Signed-off-by: Lang Cheng <chenglang@huawei.com>
Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>
Reviewed-by: Yangyang Li <liyangyang20@huawei.com>
Reviewed-by: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>