Update git submodules

* Update docs/submodules/releng from branch 'master'
  - jjb: xci: bifrost-verify: Simplify bifrost job

    We no longer test OPNFV commits that affect bifrost since these are
    being tested as part of the XCI jobs. As such, simplify the job to
    only test incoming upstream patchsets. Moreover, we need to block
    when an XCI job is running since both jobs run on the same hosts and
    create the same VMs.

    Change-Id: I5c11ae5b6a4d719ec41a6e663ddf6ecbd71ac1a5
    Signed-off-by: Markos Chandras <mchandras@suse.de>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index b74ac9b..ef89690 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit b74ac9b3ce17ba5057684588ebbf8d95465b7482
+Subproject commit ef89690c70e6bd0671ead70d31f2c94bc10edcc3