Update git submodules

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

    Change-Id: Ib3fba4d6193cfa4dfa422163561cfbc8bcfa087c
    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 d19d34c..8c680f2 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit d19d34cbae5eb3a53847d6b871cf0ac9b7920e12
+Subproject commit 8c680f2563f1da9b0f794b018329e3da83de9195