Description of problem:  interface cni0 using subnet 10.88.0.0/16 that is the same network as in our organisation. There is no way to configure cni subnet during installation.


1. First we can check where all the configuration for cni0 bridge is present: 

```
# grep -ril cni0 /etc
/etc/cni/net.d/100-crio-bridge.conf
/etc/cni/net.d/87-podman-bridge.conflist
# 
# cat /etc/cni/net.d/100-crio-bridge.conf
{
    "cniVersion": "0.3.0",
    "name": "crio-bridge",
    "type": "bridge",
    "bridge": "cni0",
    "isGateway": true,
    "ipMasq": true,
    "ipam": {
        "type": "host-local",
        "subnet": "10.88.0.0/16",
        "routes": [
            { "dst": "0.0.0.0/0" }
        ]
    }
}
# 
# cat /etc/cni/net.d/87-podman-bridge.conflist
{
    "cniVersion": "0.3.0",
    "name": "podman",
    "plugins": [
      {
        "type": "bridge",
        "bridge": "cni0",
        "isGateway": true,
        "ipMasq": true,
        "ipam": {
            "type": "host-local",
            "subnet": "10.88.0.0/16",
            "routes": [
                { "dst": "0.0.0.0/0" }
            ]
        }
      },
      {
        "type": "portmap",
        "capabilities": {
          "portMappings": true
        }
      }
    ]
}
# 
```

2. Next, we can check the source of these files:

```
# grep -ril cni0 /etc | xargs rpm -qf
cri-o-1.13.9-1.rhaos4.1.gitd70609a.el8.x86_64
podman-1.0.2-1.dev.git96ccc2e.el8.x86_64
# 
```

It looks like, this default configuration comes directly from the podman and cri-o rpms installed on the VM. This means that there is no direct control of this subnet through the ignition-config or any other installation file of Openshift.

Version-Release number of the following components:

Openshift 4.1

How reproducible:

Steps to Reproduce:
1. Install Openshift.
2.
3.

Actual results: No way to configure it in ignition file.

Expected results: Should be able to change it via ignition file.

Additional info:
Please attach logs from ansible-playbook with the -vvv flag