Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 573a52a6062f0ccf8469f3a332ecb1128a703a9d
  - Create Lakelse stable branch for Kuberef

    This change adds Lakelse stable branch
    for Kuberef.

    Signed-off-by: Rihab Banday <rihab.banday@ericsson.com>
    Change-Id: If39aca70d5bcf4cdb5a3b57d688160aeafbb90f4

diff --git a/docs/submodules/releng b/docs/submodules/releng
index dbd997e..573a52a 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit dbd997e9d9785d79201d6d06bfc268a6c95eaca9
+Subproject commit 573a52a6062f0ccf8469f3a332ecb1128a703a9d