Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Point qtip-experimental-job to zte-virtual6"
  - Point qtip-experimental-job to zte-virtual6

    Change-Id: I14dc0f19014a0f320ccf1a05c14e387b61294d8d
    Signed-off-by: Taseer Ahmed <taseer94@gmail.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 4245897..fb373ce 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 4245897311f394b2d4805337d85f28c0988320ae
+Subproject commit fb373ce59cfeab1a69a9cf4d9a2ebb18417bba05