Update git submodules

Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Merge "xci: vm: start-new-vm: Copy deployment image to clean VM"
  - xci: vm: start-new-vm: Copy deployment image to clean VM

    In order to save us some time and bandwidth we can copy the deployment
    image to the clean VM in order to be used by bifrost to prepare the
    virtual machines. Moreover, we also put our key there so we can ssh
    as the root user.

    Change-Id: Id21e19aaefde71862c21180129c664c1bf121c32
    Signed-off-by: Markos Chandras <mchandras@suse.de>