Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 2fe28e379d85a6388685d8588e84bb90d7b5f50c
  - Create opnfvdocs orinico

    Change-Id: I53466ecc4eee800b3fded60eec77e6f396aefdf8
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 3910419..2fe28e3 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 39104196379b50039ee7801514536837768112ee
+Subproject commit 2fe28e379d85a6388685d8588e84bb90d7b5f50c