netfilter: nft_set_pipapo: .walk does not deal with generations

stable inclusion
from stable-v5.10.186
commit 2a90da8e0dd50f42e577988f4219f4f4cd3616b7
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8J4KH

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=2a90da8e0dd50f42e577988f4219f4f4cd3616b7



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[ Upstream commit 2b84e215 ]

The .walk callback iterates over the current active set, but it might be
useful to iterate over the next generation set. Use the generation mask
to determine what set view (either current or next generation) is use
for the walk iteration.

Fixes: 3c4287f6 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>