Fix network_data path for dhcpless deployments
Fix network_data path for dhcpless deployments

The curent path "openstack/latest/metadata/network_data.json" is
not being used by Glean. This path must be changed to
"openstack/latest/network_data.json" as per the code here
https://opendev.org/opendev/glean/src/branch/master/glean/cmd.py#L1317-L1331

Change-Id: I7a6bb699f171585119c91d0808ff0c85d04104bf
Story: #2008042
Task: #40704

openstack/ironic,openstack/ironic