Consolidate ubuntu/debian required_defaults

sgabios is a virtual package provided by qemu-system-data. Replacing
it with qemu-system-data makes this file identical with ubuntu.

Change-Id: I0f016da347dccda5df9a9c318bf0280cb2097f68

playbooks/roles/bifrost-create-vm-nodes/defaults/required_defaults_Debian.yml

@@ -9,7 +9,7 @@ required_packages:
  - qemu-utils
  - qemu-kvm
  - qemu-system-x86
- - sgabios
+ - qemu-system-data
  - pkg-config
  - libvirt-dev
  - ovmf

playbooks/roles/bifrost-create-vm-nodes/defaults/required_defaults_Ubuntu_20.04.yml

@@ -1,17 +0,0 @@
----
-sgabios_dir: /usr/share/qemu/
-libvirt_service_name: libvirtd
-required_packages:
- - g++
- - libvirt-daemon-system
- - libxslt1-dev
- - libxml2-dev
- - qemu-utils
- - qemu-kvm
- - qemu-system-x86
- - qemu-system-data
- - pkg-config
- - libvirt-dev
- - ovmf
- - ebtables
- - dnsmasq