Honor bastion host config from inventary (#5522)

Before this commit, the bastion entry in the inventary was not honored,
so machines behind firewalls or with unrouted addresses were not
reachable for ansible.

contrib/metallb/metallb.yml

 ---
+- hosts: bastion[0]
+  gather_facts: False
+  roles:
+    - { role: kubespray-defaults}
+    - { role: bastion-ssh-config, tags: ["localhost", "bastion"]}
 - hosts: kube-master[0]
   tags:
     - "provision"
   roles:
+    - { role: kubespray-defaults}
     - { role: provision }