Description of problem:
node_exporter that can't be running on nodes that are offline/unavailable is one of the top reasons why CMO goes degraded. It would make sense to have CMO correlate the number of running node_exporter pods with the status of the nodes and not go degraded if the node_exporter pods are running on all nodes which are ready. As an example, if the cluster has N nodes with one node being not ready and (N-1) node_exporter pods are running then CMO should report Available rather than Degraded.
Version-Release number of selected component (if applicable):
Always when nodes are offline.
Steps to Reproduce:
Backport clone of https://issues.redhat.com/browse/OCPBUGSM-32497