RDMA/hns: Add reset process for function-clear

If the hardware is resetting, the driver should not perform
the mailbox operation.Function-clear needs to add relevant judgment.

Signed-off-by: Lang Cheng <chenglang@huawei.com>
Link: https://lore.kernel.org/r/1566393276-42555-7-git-send-email-oulijun@huawei.com


Signed-off-by: Doug Ledford <dledford@redhat.com>