Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "[QTIP] Add a new variable "SUT" in project"
  - [QTIP] Add a new variable "SUT" in project

    QTIP test runs against with host and vnf.

    Change-Id: I863cb48356f6ba74043b51ebfae8e5ff2f241abc
    Signed-off-by: zhihui wu <wu.zhihui1@zte.com.cn>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 146464f..4a3d739 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 146464fc62732f55904b74e5a2327fd2f257114f
+Subproject commit 4a3d73952f8c5b4b4a308ebfa108a84f0c6b3c0e