collect only specific network facts

When running a playbook with become: true, it also runs the facts
module with sudo, so ansible_user_dir will have the value of the
root user, rather than the expected home directory of the
ansible_ssh_user.

This can create issues in further tasks as ansible cache is used,
variables like ansible_user_dir can persist when next tasks run.

~~~
fatal: [undercloud]: FAILED! => {"changed": false, "error":
"[Errno 13] Permission denied:
'/root/tripleo_undercloud_install.sh'", "msg": "Unable to
 output shell script /root/tripleo_undercloud_install.sh:
 [Errno 13] Permission denied: '/root/tripleo_undercloud_install.sh'"}
~~~

With this patch, We are modfying making two changes:-

1) Removing not required become: true as interfaces information can be
captured as normal user.

2) Modifying the setup: module to only collect particular network
fact subsets and not even the min subset.

Change-Id: Ib167b88b03f01bb8945c53cd000b5fcac85dd320

roles/baremetal-prep-virthost/tasks/remove_ens3.yml

@@ -1,8 +1,7 @@
 ---
 - name: Discover if ens3 interface exists
-  become: true
   setup:
-    gather_subset: network
+    gather_subset: "!all,!min,network"
   register: net
 
 - name: Check if ifcfg-ens3 exists