Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [maas] Fix class ordering for ipv6.disable dup

    Include class disabling IPv6 first, so our override is last.

    Change-Id: I91f8cb48ab2eaef54eb98705fc97ab9910c3666f
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 54ebfaf..ce86651 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 54ebfaf561693186580cacf259804f7968bec0fd
+Subproject commit ce86651f68402b7ba8ac193461957b1088696c63