Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "[baremetal] MaaS: Fix DHCP dynamic reserved range"
  - [baremetal] MaaS: Fix DHCP dynamic reserved range

    - patch MaaS to default to `DHCP` instead of `AUTO` for physical
      PXE interfaces (all IPs will be handed out by MaaS DHCP *inside* the
      defined dynamic DHCP IP range);
    - reduce range to silence bogus MaaS warning about address exhaustion;
    - regenerate pod_config.yml.example to reflect the changes;
    - drop `opnfv_infra_maas_pxe_address` (duplicate of
      `opnfv_infra_maas_node01_deploy_address`);
    - add `opnfv_infra_config_pxe_address` for future usage;
    - while at it, fix missing patch copyright;

    JIRA: FUEL-316

    Change-Id: I81fad333e77f7c8508cd2b2b267c7b39c130e3e1
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index a7fcdb9..25536c1 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit a7fcdb99e7b3cc9a2952c07da2e5e17be9f83c0d
+Subproject commit 25536c1e20bdde947b387830556e1d4c95590f99