Update git submodules

Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Merge "xci: Drop custom XCI certificates"
  - xci: Drop custom XCI certificates

    OSM requires a CA even when we create a self-signed certificate. We
    don't actually need to do that since HAproxy and friends can create the
    whole chain for us, so we can finally get rid of this playbook.

    installer-type:osa
    deploy-scenario:os-nosdn-nofeature

    Change-Id: I14a3adbe3492cd6c562c5167c42dd45756e8e3dd
    Signed-off-by: Markos Chandras <mchandras@suse.de>