Update git submodules

Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Update CI Resources and Requirements"
  - Update CI Resources and Requirements

    Indicates what requirements each resource type should meet in order to
    be considered part of OPNFV CI along with listing of the resources
    available.

    Includes a list of labels applied to servers and their intended use.

    JIRA: RELENG-403
    Change-Id: I0ba2671e95e29141d051019938fba930a42e7f56
    Signed-off-by: Trevor Bramwell <tbramwell@linuxfoundation.org>