Description of problem:
When upgrade ocp3.5 masters with openshift_excluder and docker_excluder enabled on all hosts, upgrade_control_plane playbook will finish with one failed task caused by fatal error that no available openshift package found on dedicated node. 

TASK [Fail when unable to determine available OpenShift RPM version] ***********
task path: /usr/share/ansible/openshift-ansible/playbooks/common/openshift-cluster/upgrades/pre/verify_upgrade_targets.yml:27
skipping: [openshift-119.x.x.x] => {
    "changed": false,
    "skip_reason": "Conditional check failed",
    "skipped": true
}
fatal: [openshift-118.x.x.x]: FAILED! => {
    "changed": false,
    "failed": true,
    "invocation": {
        "module_args": {
            "msg": "Unable to determine available OpenShift RPM version"
        },
        "module_name": "fail"
    }
}

MSG:

Unable to determine available OpenShift RPM version

<--snip-->
PLAY RECAP *********************************************************************
localhost                  : ok=25   changed=0    unreachable=0    failed=0
openshift-118.x.x.x : ok=60   changed=4    unreachable=0    failed=1
openshift-119.x.x.x : ok=515  changed=51   unreachable=0    failed=0


Version-Release number of selected component (if applicable):
atomic-openshift-utils-3.6.80-1.git.0.807fc98.el7.noarch

How reproducible:
always

Steps to Reproduce:
1. install ocp3.5(one master/node + one node)
2. install excluders on all hosts
3. run upgrade_control_plane.yml to upgrade masters first
# ansible-playbook -i hosts /usr/share/ansible/openshift-ansible/playbooks/byo/openshift-cluster/upgrades/v3_6/upgrade_control_plane.yml

Actual results:
Upgrade finished with one failed error on dedicated node.

Expected results:
Upgrade should succeed with no failure.

Additional info:
Disable_master_excluders.yml only run on master host, but verify_upgrade_targets.yml targets on both masters and hosts.