RDMA/hns: adjust the structure of RoCE bonding driver

driver inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I63IM5



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This patch deletes some used variables, encapsulates repeated codes in a
new function get_upper_dev_from_ndev and adjusts the structure of
hns_roce_bond_event to make the logic clearer.

Fixes: e62a2027 ("RDMA/hns: support RoCE bonding")
Signed-off-by: Junxian Huang <huangjunxian6@hisilicon.com>
Reviewed-by: Yangyang Li <liyangyang20@huawei.com>
Reviewed-by: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>