Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - xci: Improve scenario bootstrapping process

    It's best to check whether the scenario/distro/flavor combination is
    supported before spending time cloning all the scenarios. Moreover,
    we can record the scenario information as a local fact so we can use
    it during the deployment later on.

    Change-Id: I1971444c6c6302a844f44ea651ad3b83c4da435c
    Signed-off-by: Markos Chandras <mchandras@suse.de>
  - xci: playbooks: Simplify scenario overrides mechanism

    Now that releng-xci does not have any internal scenarios anymore, we can
    simplify the way we plug scenarios to XCI. We keep cloning scenarios in
    the cache directory but we also allow users to pass a special
    'xci_scenarios_overrides' variable similar to the
    'opnfv_scenario_requirements.yml' file to allow them to override
    specific keys of the dictionaries. This can be used by Jenkins to test
    incoming changes by altering the defaults values. For example, when
    we want to test a Gerrit change we can create a file called foobar.yml
    with the following contents

    xci_scenarios_overrides:
      - scenario: os-odl-sfc
          version: 9fa5400012e02408b416eb7bd26307e7d179abce
          refspec: refs/changes/79/55879/7

    and load it using

    XCI_ANSIBLE_PARAMS="-e @foobar.yml"

    This will make XCI checkout the refspec that we want instead of the
    default version.

    Change-Id: Ida49910b4c79b843582ddd70c00063fe9bc90dd4
    Signed-off-by: Markos Chandras <mchandras@suse.de>

diff --git a/docs/submodules/releng-xci b/docs/submodules/releng-xci
index 15be5eb..3699202 160000 (submodule)
--- a/docs/submodules/releng-xci
+++ b/docs/submodules/releng-xci
@@ -1 +1 @@
-Subproject commit 15be5eb8da9881428ea1635a3184c39f63dfaf80
+Subproject commit 36992029ed404569304187779492a4d737d6fc50