Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Do not set bashisms when calling build.sh

    The maintainer can decide to set errexit nounset or pipefail
    Plus, this fails as pipefail is a bashism and shell: calls sh

    Change-Id: Ibac052fddce7e9a3eb7c536e08c64d9dad1a7a0a
    Signed-off-by: agardner <agardner@linuxfoundation.org>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index b72f926..af8f5f0 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit b72f9268dd7194d1ed05a9f5b1781a724271c093
+Subproject commit af8f5f0fd827ef616c891945615c23fe79df862d