Update git submodules

* Update docs/submodules/releng from branch 'master'
  - jjb: xci: bifrost-verify.sh: Respect bifrost test failures

    Make sure that failures during bifrost deployments are being
    reported properly on Jenkins.

    Change-Id: I333d27147caf7598665157c703907572e48041c0
    Signed-off-by: Markos Chandras <mchandras@suse.de>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 467fd46..6bec6e4 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 467fd46ba8e91795e7471f12edb44d68693e57ab
+Subproject commit 6bec6e4eda96b4d938efd1d1a0702295fae2c806