Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Merge "XCI: Bump OpenStack Ansible SHAs"
  - XCI: Bump OpenStack Ansible SHAs

    Change-Id: If5e4ff731b2bf59e44b753ce0574f25639694162
    Signed-off-by: Markos Chandras <mchandras@suse.de>

diff --git a/docs/submodules/releng-xci b/docs/submodules/releng-xci
index 0234db9..9145384 160000 (submodule)
--- a/docs/submodules/releng-xci
+++ b/docs/submodules/releng-xci
@@ -1 +1 @@
-Subproject commit 0234db9d76656d8f28ba3ee11367e08703ccd769
+Subproject commit 91453843869e5092dc62a10c5644c2336a70fa2d