Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 5b4b987d68d6ad0e35bbb247d386ba66c37e66dc
  - Use common build for containers

    Change-Id: I20c2fddd33f030bddaa210a65c8d17e1c8631c48
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 10076a9..5b4b987 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 10076a94d789772e73f2d6da6da1729c05dc3950
+Subproject commit 5b4b987d68d6ad0e35bbb247d386ba66c37e66dc