[RFE] Support MACsec in RHCOS/RHOCP

1. Proposed title of this feature request
Requesting a MACsec feature in RHCOS/OCP.

2. What is the nature and description of the request?
There is a doc[1] for RHEL8, but none for CoreOS. The customer wants to enable/configure MACsec in RHCOS/RHOCP to secure traffic between nodes and switches.

3. Why does the customer need this? (List the business requirements here)
The customer is required to secure all traffic between the cluster and the network switch.

4. List any affected packages or components.
Red Hat CoreOS
Red Hat Openshift Cluster Platform

[1]
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/configuring_and_managing_networking/assembly_using-macsec-to-encrypt-layer-2-traffic-in-the-same-physical-network_configuring-and-managing-networking