netfilter: nftables: skip hook overlap logic if flowtable is stale

stable inclusion
from stable-5.10.29
commit 8a57256e0548fee9b9918c5a7bffc8770dcc5afa
bugzilla: 51789

--------------------------------

[ Upstream commit 86fe2c19 ]

If the flowtable has been previously removed in this batch, skip the
hook overlap checks. This fixes spurious EEXIST errors when removing and
adding the flowtable in the same batch.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Acked-by:   Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>