Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Merge "xci: Check XCI playbooks using ansible-lint"
  - xci: Check XCI playbooks using ansible-lint

    The ansible-lint tool can help with maintaining consistency across all
    the XCI playbooks, so lets introduce it early in the process to capture
    common mistakes before the actual XCI deployment is executed. This
    however needs to run after all the scenarios repositories have been
    cloned and configured.

    Change-Id: I28104429e3ac0cdbc48a003b163f4fb8c3acd8a7
Link: https://github.com/willthames/ansible-lint
    Signed-off-by: Markos Chandras <mchandras@suse.de>

diff --git a/docs/submodules/releng-xci b/docs/submodules/releng-xci
index 14228ae..efc57cd 160000 (submodule)
--- a/docs/submodules/releng-xci
+++ b/docs/submodules/releng-xci
@@ -1 +1 @@
-Subproject commit 14228ae572f272b03b535271414772f2206208c8
+Subproject commit efc57cd6b442eb16cddd1f383591aba87f72694d