Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [dpdk] Remove user/group setting for ovs rundir

    The proper patches have been merged into upstream (nova/neutron
    formulas, system reclass) to use a separate dir for vhost_user sockets.

    Change-Id: Iba8d8a9a05c5ab681b5b5ffbea786dca92704c82
    Signed-off-by: Michael Polenchuk <mpolenchuk@mirantis.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index fbf520a..5ed31a0 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit fbf520aa48b44b4b6cec070cc46fca007a41661a
+Subproject commit 5ed31a007826052a723cb573f7ed49a7473699f6