netfilter: nftables: remove redundant assignment of variable err

stable inclusion
from stable-v5.10.140
commit cd962806c4493eec8a0da72d1df227dac28d3e15
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I63FTT

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=cd962806c4493eec8a0da72d1df227dac28d3e15



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[ Upstream commit 626899a0 ]

The variable err is being assigned a value that is never read,
the same error number is being returned at the error return
path via label err1.  Clean up the code by removing the assignment.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>