Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 79c54d570606a98b143b6663d3262517455775ad
  - Set arm_dirs in Functest K8s docker builds

    Change-Id: I1a806294b4a90e12a4dd6f83e5a0514444912aa3
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 75dfb43..79c54d5 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 75dfb43003c69bbbb5f562afc007b4256b85c5e7
+Subproject commit 79c54d570606a98b143b6663d3262517455775ad