Backport some important fixes.
    
    Backported the following fixes:
     - Don't suppress localport traffic directed to external port (#1974062)
     - northd: Fix multicast table full comparison. (#1979870)
     - northd-ddlog: Fix IP family match for DNAT flows.
     - Disable ARP/NA responders for vlan-passthru switches
     - tests: Fix "vlan traffic for external network with distributed..."
     - ovn-controller: Fix port group I-P when they contain non-vif ports.
     - system-tests: Fix the test file.
     - northd: Swap src and dst eth addresses in router egress loop.
     - ovn.at: Fix test "virtual ports -- ovn-northd-ddlog"
    
    Signed-off-by: Numan Siddique <numans@ovn.org>