RDMA/hns: Remove asynchronic QP destroy

mainline  inclusion
from mainline-v5.2
commit 57425822
category: bugfix
bugzilla: NA
CVE: NA

Verbs destroy callbacks are synchronous operations and can't be delayed.
The expectation is that after driver returned from destroy function, the
memory can be freed and user won't be able to access it again.

Ditch workqueue implementation used in HNS driver.

Fixes: d838c481 ("IB/hns: Fix the bug when destroy qp")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: oulijun <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Shunfeng Yang <yangshunfeng2@huawei.com>
Reviewed-by: chunzhi hu <huchunzhi@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>