Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Create Stable Branch Jobs for yardstick"
  - Create Stable Branch Jobs for yardstick

    Change-Id: I5e59b6240b1e614fc6c06f918054813b7e5758cf
    Signed-off-by: jenkins-ci <jenkins-opnfv-ci@opnfv.org>
    Signed-off-by: Trevor Bramwell <tbramwell@linuxfoundation.org>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 58126f0..34fdd50 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 58126f06600112dd592a9c8776cca7770580ac8f
+Subproject commit 34fdd5026155a29f530bbfd3c765639bebde3b25