Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Set ODL tests and refstack client refs

    To prepare F-release, we should set git commit ids for these
    dependencies which follow the rolling release model (master).

    Change-Id: I3c791040ea5ec700cfa845ae642e6d862c49281f
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 530c678..d2620ae 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 530c678677cc314c159936fdf5e121e83fc1d0cc
+Subproject commit d2620ae72be08f83548be81fa80a418f2250da28