Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Integrate functest with ARM Architecture"
  - Integrate functest with ARM Architecture

    Reads architecture of first compute node found on MCP installer
    and sends it as env variable when creating the conatiner.
    It is needed by https://gerrit.opnfv.org/gerrit/#/c/39991/
    JIRA: ARMBAND-279

    Change-Id: I7eec485507bd182190e95c0478182f506db4c821
    Signed-off-by: Delia Popescu <delia.popescu@enea.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 17ff086..75ad867 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 17ff08645fc8e6e8b2c0bc22152f2cab44d3f92b
+Subproject commit 75ad867556d9475c7881863dfb44ccdcc154228b