[RFE] filter the nodes by a label selector

[ptrnull]

The oc debug node is pretty heavy in time consumption, it could happen that a user wants to check only a specific group of nodes or a single node. A parameter like the following would be really useful:
-f sriov

For example, to run the checks on the nodes with the label sriov will get the following nodes and execute the checks only on this nodes:

$ oc get node -l sriov
NAME                STATUS   ROLES    AGE    VERSION
rna1-master-0.*   Ready    worker   104d   v1.17.1
rna1-master-1.*   Ready    worker   104d   v1.17.1
rna1-master-2.*   Ready    worker   104d   v1.17.1