Update git submodules

Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "[FN VMs] remove graphics"
  - [FN VMs] remove graphics

    Since VCP VMs (created via salt formula) do not have a video
    controller defined in their domain XMLs, network devices end on
    different PCI slots and hence have different names assigned
    (ens2+ vs foundation node VMs, which start with ens3).

    To align network interface names for VMs on jumpserver vs kvm nodes,
    and reduce confusion, remove the video controller from FN VMs.

    This allows some cleanup:
    - drop extra AArch64 args from virt-install;
    - unify 'opnfv_vcp_vm_*' and 'opnfv_fn_vm_*' variables;

    Change-Id: I0d108b00914b3eaaa03b67c652174f8ed4573118
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>