Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [baremetal] Move VCP iface config to own yml

    - move linux.network.interface definitions to their own classes, which
      also removes the previous requirement of defining {dhcp,single}_nic
      parameters in classes that don't actually use them;
    - drop now useless {dhcp,single}_nic parameters;
    - expand linux_{dhcp,single}_interface macros, since they cause issues
      with reclass dict-merge while attempting to override sub-vars (i.e.
      it's not possible to set 'enabled: false' via reclass interpolation);

    JIRA: FUEL-310

    Change-Id: I29d921f545e761de335a60e242a4523d13b06c78
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 9eb05da..2fc4b88 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 9eb05da8bc5618e4b95d396fcc932a7c0abb3bd6
+Subproject commit 2fc4b8890ef1ad456ac1ff421f33e005ae0484be