9a85217412
Many changes to the nftables backend which will be used in the follow-up PR with #4421. 1. Add support for chain policy: drop/accept. 2. Properly handle match on all IPs in the set (`0.0.0.0/0` like). 3. Implement conntrack state matching. 4. Implement multiple ifname matching in a single rule. 5. Implement anonymous counters. Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com>