RDMA/hns: Adjust the order in which irq are requested and enabled

It should first alloc workqueue and request irq, and finally enable irq.

Link: https://lore.kernel.org/r/1629985056-57004-6-git-send-email-liangwenpeng@huawei.com


Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>