Update git submodules

Update git submodules

* Update docs/submodules/fuel from branch 'stable/euphrates'
  - Merge "[baremetal] Re-assign mgmt network to proxy nodes" into stable/euphrates
  - [baremetal] Re-assign mgmt network to proxy nodes

    - extend arch-specific list of predefined VM iface names (2 -> 3);
    - add extra vnet iface for prx0* VCP VMs, connected to br-ctl (mgmt);
    - add mgmt address to pod_config.yml template (and sample);
    - add mgmt address to reclass.storage prx nodes;

    JIRA: FUEL-302

    Change-Id: I17ce65eade7f69219fc27264363364e3c47d8f3f
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
    (cherry picked from commit 35041f05e790f8c13782eb4956b991a97fdec853)