Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Merge "XCI: k8s: Add support for CentOS distro"
  - XCI: k8s: Add support for CentOS distro

    Kubespray already supports the CentOS distribution so make the
    necessary changes to allow it to work in XCI.

    Change-Id: I3cf1db055a5fd563b107b46456bc3e18eeafb3ab
    Co-authored-by: Markos Chandras <mchandras@suse.de>
    Signed-off-by: wutianwei <wutianwei1@huawei.com>

diff --git a/docs/submodules/releng-xci b/docs/submodules/releng-xci
index d49926b..1cc81c1 160000 (submodule)
--- a/docs/submodules/releng-xci
+++ b/docs/submodules/releng-xci
@@ -1 +1 @@
-Subproject commit d49926b405d6b24d40497cbee68ce50c82bad222
+Subproject commit 1cc81c151829ec519c04f3210c73f87b639341df