Update git submodules

Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Merge "xci: Wipe repositories at the beginning of the deployment"
  - xci: Wipe repositories at the beginning of the deployment

    We should not wipe the repositories in the localhost playbooks since
    it makes it somewhat hard to debug problems. We should do that at the
    beginning of the deployment to ensure that we start without any stale
    git data.

    Change-Id: I70b2ac77284a9ca304d6aa68dbf1654f59260dc4
    Signed-off-by: Markos Chandras <mchandras@suse.de>