RDMA/hns: Support kernel ULP querying HW ID

driver inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I8C2IP



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Add API rdma_query_hw_id() to enable kernel-mode applications to
query the HW ID of the current device.

Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>