Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 609c775b7eda2177d6244b9b1b37c93d772b744e
  - Force releng release job retrigger

    Change-Id: Ia63e418ac1684fea7ee06bddaba227f7c83b7f98
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 6c141da..609c775 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 6c141da425fb73757c19cf102957253ff35425c3
+Subproject commit 609c775b7eda2177d6244b9b1b37c93d772b744e