RDMA/hns: Validate the pkey index

mainline inclusion
from mainline-v5.16-rc2
commit 2a67fcfa
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4QOTS
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma.git/commit/?id=2a67fcfa0db6b4075515bd23497750849b88850f

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Before query pkey, make sure that the queried index is valid.

Fixes: 9a443537 ("IB/hns: Add driver files for hns RoCE driver")
Link: https://lore.kernel.org/r/20211117145954.123893-1-kamalheib1@gmail.com


Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
sigend-off-by: Guofeng Yue <yueguofeng@hisilicon.com>

Reviewed-by: Yangyang Li <liyangyang20@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>