Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - mcp: salt-formulas: opendaylight: AArch64 leveldb

    ODL requires native leveldbjni support on architectures like AArch64,
    provided as a Debian package in ODL Team Nitrogen PPA.

    Only systemd is supported (unlikely to change).

    JIRA: ARMBAND-387

    Change-Id: Ie7f2955c6574ab4584ed0c207b42ed7ab7261561
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 7f797f1..57175f4 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 7f797f1b5a9340d24d700879abca6b39413e7375
+Subproject commit 57175f45f6ae9c2ee2adf02ea30a75c0ab956206