Update git submodules

* Update docs/submodules/stor4nfv from branch 'master'
  - Update entry_point to conform with Xtesting

    Functest is being updated to Xtesting 0.60 which leverages on
    stevedore [1].

    [1] https://docs.openstack.org/stevedore/latest/

    Change-Id: I39bc26b6a7cd5b0aee071d1d543701c1adf9acc9
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/stor4nfv b/docs/submodules/stor4nfv
index df4ff81..828acdd 160000 (submodule)
--- a/docs/submodules/stor4nfv
+++ b/docs/submodules/stor4nfv
@@ -1 +1 @@
-Subproject commit df4ff81d7e0d296b74c17957817cba4137756db8
+Subproject commit 828acdd1d5c5c2aeef287aa69e473bf44fcbce70