Resolv-prepender doesn't create signal file on reboot

Description of problem:

There is a problem with the logic change in https://github.com/openshift/machine-config-operator/pull/4196 that is causing Kubelet to fail to start after a reboot on OpenShiftSDN deployments. This is currently breaking all of the v4 metal jobs.

Version-Release number of selected component (if applicable):

    4.16

How reproducible:

    Always

Steps to Reproduce:

    1. Deploy baremetal cluster with OpenShiftSDN
    2.
    3.
    

Actual results:

    Nodes fail to join cluster

Expected results:

    Successful cluster deployment

Additional info: