Update git submodules

* Update docs/submodules/releng from branch 'master'
  - add yardstick hunter ci jobs

    Change-Id: Ibfd85198ce937fbe32f9ed8593d65326f45bb293
    Signed-off-by: rexlee8776 <limingjiang@huawei.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 668072f..5f6d56e 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 668072f6a6f76381f7babc9950e99e935db1b6ed
+Subproject commit 5f6d56ef2210fdf09ed86cd2c9946222010e36ed