Update git submodules

* Update docs/submodules/releng from branch 'master'
  to d8a552bb607a175dfccfca72173a17cd06e77165
  - Build other multiarch images

    Change-Id: I750ec05cf3fd7da28bdb09895b5bf1541981835c
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index abe0272..d8a552b 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit abe0272b8f19caf7928d85597b6c1fa54fd7c936
+Subproject commit d8a552bb607a175dfccfca72173a17cd06e77165