Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [baremetal] maas state: Wait for all nodes online

    After MaaS reports baremetal provisioning finished successfully,
    check that all nodes are online before attempting a `sync_all`.

    Change-Id: I6ba4b3e4ba5b5258ace4da8c39e0fc77354885e3
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 51f374b..b9918f1 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 51f374b055999fbc121b624424c21ee45d061538
+Subproject commit b9918f1f8df52c52cd2ab76eec3b540b37789e55