Remove Docker role, CoreOS has Docker preinstalled

metal/main.yml

@@ -4,11 +4,6 @@
   roles:
     - pxe-boot
 
-- name: Provision
-  hosts: metal
-  roles:
-    - docker
-
 - name: Create Terraform state storage
   hosts: metal[0]
   roles:

metal/roles/docker/tasks/main.yml

@@ -1,9 +0,0 @@
-- name: Install Docker
-  dnf:
-    name: docker
-
-- name: Start Docker service
-  systemd:
-    name: docker
-    state: started
-    enabled: yes