Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "[jump] Add simple check for required Linux bridges"
  - [jump] Add simple check for required Linux bridges

    - MaaS requires PXE/admin to be a Linux bridge;
    - if virtual nodes are present, they should be hooked to a proper
      Linux bridge for the Public network, but only throw a warning if
      not (and create a mock public virsh network instead);
    - if both virtual and baremetal nodes are present, Public bridge is
      indirectly mandatory (we can't mock it);

    JIRA: FUEL-339

    Change-Id: Idfe99d66c49eadc56cb3d94ca4db3467fb76d388
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 695c4d2..a9d3798 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 695c4d2d08caf1032645b41746fa92a42cc29edc
+Subproject commit a9d37983b3796adbcd0e2099487b9d14f6484e1d