Add iscsi metrics to Openshift monitoring

1. Proposed title of this feature request 

Add iscsi metric to Openshift monitoring

2. What is the nature and description of the request?

Enable monitoring of iscsi metrics to Openshift monitoring/Prometheus

3. Why does the customer need this? (List the business requirements here)

One of Openshift Telco customers wants to monitor iscsi metrics on the node using openshift inbuilt prometheus, they are deploying workloads with iscsi as a backend and they want to take a look at the iscsi metrics.

The customer pointed to the following documentation https://snapcraft.io/install/prometheus-iscsi-exporter/rhel#install

We advised them to not proceed with this solution since it will be outside of Redhat scope of the Service Level Agreement and support procedures, we suggested they instead to wait, so we can open this RFE.
4. List any affected packages or components.

Openshift platform 4.12