Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "unify data existence check"
  - unify data existence check

    Change-Id: I2ee4c3be6f34ce12530450cd22f2561c458685f9
    Signed-off-by: SerenaFeng <feng.xiaowei@zte.com.cn>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 01b0d7c..139e621 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 01b0d7cfb0cef5a399446221e9bff5ccfdabe6f3
+Subproject commit 139e621ba828d039cee1066ed090e2d7b39bc6b1