Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Update Functest jjbs (Alpine 3.9)

    Change-Id: If636802e410e27e6d3811a7d959ce5dbf12d17ce
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 1349eae..fec1da8 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 1349eae9fc86e5acad31565785dc8ff4f5afc51f
+Subproject commit fec1da85bea695e5e23464841762cd1a78c8718e