RDMA/mlx5: Add missing check for return value in get namespace flow

stable inclusion
from stable-v5.10.137
commit 53da1f0fa0e2e197df1a95729a15b27f7b2b911c
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=53da1f0fa0e2e197df1a95729a15b27f7b2b911c

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[ Upstream commit c9776457 ]

Add missing check for return value when calling to
mlx5_ib_ft_type_to_namespace, even though it can't really fail in this
specific call.

Fixes: 52438be4 ("RDMA/mlx5: Allow inserting a steering rule to the FDB")
Link: https://lore.kernel.org/r/7b9ceda217d9368a51dc47a46b769bad4af9ac92.1659256069.git.leonro@nvidia.com


Reviewed-by: Itay Aveksis <itayav@nvidia.com>
Signed-off-by: Maor Gottlieb <maorg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>