Clean up the default variables.

defaults/main.yml

@@ -27,11 +27,6 @@ sysctl_custom_options: []
 
 ubuntu_configure_additional_interfaces: false
 ubuntu_configure_additional_int_dhcp_overrides: true
-ubuntu_second_int_name: "enp4s0"
-ubuntu_netplan_interfaces:
-  - name: "{{ ubuntu_second_int_name }}"
-    dhcp4: true
-    dhcp_overrides: true
 disable_ipv6: false
 ipv6_sysctl_value: 1
 ipv6_sysctl_file: /etc/sysctl.d/10-ipv6-disable.conf