RDMA/hns: Remove unnecessary check for the sgid_attr when modifying QP

mainline inclusion
from mainline-for-linus
commit c2fcafa7
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5CHIG
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git/commit/?id=c2fcafa78a33576b7fe47f5e4f85d413a62c2fe2

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The sgid_attr cannot be null in this scenario. This judgment is redundant.

Fixes: 606bf89e ("RDMA/hns: Refactor for hns_roce_v2_modify_qp function")
Link: https://lore.kernel.org/r/20220409083254.9696-2-liangwenpeng@huawei.com


Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>
Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Zhengfeng Luo <luozhengfeng@h-partners.com>
Reviewed-by: Yangyang Li <liyangyang20@huawei.com>
Reviewed-by: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>