Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 8f61bcc5c0491f183e4458960a72f37d48f95d9f
  - Verify all Functest containers

    It also checks the arm4 containers built in OPNFV.

    Change-Id: I7897ac34606c848b1828953486f7ee2ce340ee27
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index ab5ad58..8f61bcc 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit ab5ad58dee26138d22f88f25ec542e5aa8b3eed7
+Subproject commit 8f61bcc5c0491f183e4458960a72f37d48f95d9f