Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 74113ef6ec1f9beb7c482b1910d8a2d9c2fef332
  - Set HOME to /home/ubuntu (airship)

    https://github.com/airshipit/treasuremap/blob/master/tools/openstack#L10
    https://build.opnfv.org/ci/job/airship-deploy-daily-latest/2/console

    Change-Id: If783af88fed8aba140a4f8f41e19b4f82838837f
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index a87ae15..74113ef 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit a87ae1563709f0d1c105cc4f510e481e1e0d724a
+Subproject commit 74113ef6ec1f9beb7c482b1910d8a2d9c2fef332