RDMA/hns: Clean definitions of EQC structure

Remove unused members in EQ context structure.

Fixes: 782832f2 ("RDMA/hns: Simplify the function config_eqc()")
Link: https://lore.kernel.org/r/1624011020-16992-7-git-send-email-liweihang@huawei.com


Signed-off-by: Xi Wang <wangxi11@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>