Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - Merge "[maas] Adopt node role from scenario definitions"
  - [maas] Adopt node role from scenario definitions

    Instead of hardcoding kvm hostnames in maas machine definitions,
    read node roles/hostnames from current scenario and map them
    accodingly.

    JIRA: FUEL-382

    Change-Id: I15d52e299e0353971f8d0c7da853c571ad5410da
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index ce2d5fc..ab9ccfd 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit ce2d5fc4b6b4cda93f858adc5ac6ab991495e8a9
+Subproject commit ab9ccfdc387c02a42c89e8770c26634f3e6c5ceb