ncm-network: nmstate - provide backward capability support for vlan interface in nmstate.

[aka7]

currently nmstate supports vlan interface configuration if its defined in following format.

"/system/network/interfaces/eth0.123"
"/system/network/interfaces/eth0.123/vlan"=true

see vlaninterface.pan in test/

Looking at network.pm code, it supports vlan interface if interface name is given with prefix vlan, such as this.

"/system/network/interfaces/vlan0" = create("defaultinterface");
prefix "/system/network/interfaces/vlan0";
"device" = "eth0.123";
"physdev" = "eth0";
"route/0" = dict("address", "1.2.3.4");

we use the format "/system/network/interfaces/eth0.123" so not a issue for us, but this may have impact on anyone else who is using vlan in previous release and want to move to nmstate.

Also nmstate code assumes interface name and device name might always be same in few places, which won't be case here, so may need few fixes on this along the way.

• The version of the component you are using (rpm -q $component) ncm-network-23.6.0

• What OS version you are using (/etc/redhat-release or similar) Red Hat Enterprise Linux release 9.3 (Plow)

• Steps required to reproduce the problem switch to use nmstate backend for previously configured vlan host.

• Actual result versus expected result interface configured with right vlan id etc in nmstate.