Update git submodules

* Update docs/submodules/fuel from branch 'stable/euphrates'
  - Merge "Run packages upgrade on openstack nodes only" into stable/euphrates
  - Run packages upgrade on openstack nodes only

    Change-Id: I53ac0be519df1bb39a6a56e236285fce95228bd4
    Signed-off-by: Michael Polenchuk <mpolenchuk@mirantis.com>
    (cherry picked from commit c15004f402555df4886b18bba9a837288c6ef250)

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index 79af134..533b81d 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit 79af1346fdd99e2186c45b2fd696d4ed6feb91cf
+Subproject commit 533b81df35acd7c2f16cd347cf3167583e870d38