Use cloud-init to pass data to rhel vm

[lstocchi]

The current podman code uses ignition to pass ssh keys, system unit file and more ... However, rhel kvm works with cloud-init.

On Mac we could leverage vfkit and feed it with the cloud-init config file.
Not sure about hyper-v

[lstocchi]

An example of cloud-init config file that mimics what podman does

#cloud-config
users:
  - name: core
    sudo: ALL=(ALL) NOPASSWD:ALL
    shell: /bin/bash
    groups: users
    lock_passwd: false
    ssh_authorized_keys:
      - ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIDAcKzAecDf0R0mrLhO2eswdq6YRpLUFN4JNonl71Dud
ssh_pwauth: true
chpasswd: { expire: false }
rh_subscription:
  username: <email>
  password: <psw>
packages:
  - socat
write_files:
- path: /etc/systemd/system/ready-macadam.service
  owner: root:root
  permissions: 0644
  content: |
    [Unit]
    After=sshd.socket sshd.service
    OnFailure=emergency.target
    OnFailureJobMode=isolate
    Requires=dev-virtio\x2dports-vsock.device

    [Service]
    Type=oneshot
    RemainAfterExit=yes
    ExecStart=/bin/sh -c '/usr/bin/echo Ready | socat - VSOCK-CONNECT:2:1025'

    [Install]
    RequiredBy=default.target

The rh_subscription is currently needed as the rhel image provided on access.redhat.com does not come with socat included and we need to install it