Update git submodules

* Update docs/submodules/releng from branch 'master'
  to cf8eb1fc02d4c7fdf74813c55ab466481f3ddf23
  - Precise platform in docker calls

    Change-Id: I37df3665cab3e5335815eacf621b3b4ee4808196
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 8676fd8..cf8eb1f 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 8676fd889c30b0941df731020738806711307baf
+Subproject commit cf8eb1fc02d4c7fdf74813c55ab466481f3ddf23