selftests: netfilter: Test nf_tables audit logging

[ Upstream commit e8dbde59

 ]

Compare NETFILTER_CFG type audit logs emitted from kernel upon ruleset
modifications against expected output.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Stable-dep-of: 0d880dc6

 ("netfilter: nf_tables: Deduplicate nft_register_obj audit logs")
Signed-off-by: Sasha Levin <sashal@kernel.org>