Update git submodules

Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "fuel, armband: Add post mortem log collection"
  - fuel, armband: Add post mortem log collection

    Debugging test suite failures is often hard without physical access
    to the POD, and even then the environment might be automatically
    redeployed before successfully debugging the problem.

    So, collect all contents of </var/log> from all cluster nodes
    (including the Salt Master node) after all test suites have been
    executed as part of the CI job.

    Change-Id: Ie5e2526c74f4ed21be9c76c6f6101eb3f434be36
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>