[OVN] metadata does not work when using neutron-dhcp-agent for baremetal ports

When using neutron-dhcp-agent for Ironic/baremetal ports - DHCP injects a route to 169.254.169.254 via the routers ip.
That's incorrect, because neutron ovn metadata agent is listening on a dedicated port (network:distributed).

Example:

# ip r l
default via 10.209.0.1 dev eno1
10.209.0.0/16 dev eno1 proto kernel scope link src 10.209.3.225
169.254.169.254 via 10.209.0.1 dev eno1
172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown

ping 169.254.169.254
PING 169.254.169.254 (169.254.169.254) 56(84) bytes of data.
^C
--- 169.254.169.254 ping statistics ---
2 packets transmitted, 0 received, 100% packet loss, time 1017ms

# ip r d 169.254.169.254
# ip r a 169.254.169.254 via 10.209.0.2

# curl 169.254.169.254
1.0
2007-01-19
2007-03-01
2007-08-29
2007-10-10
2007-12-15
2008-02-01
2008-09-01
2009-04-04

OVN version: 21.12
OVS version: 2.16.0
OpenStack release: Wallaby