Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "fuel, armband: Move mcp.rsa to /var/lib/opnfv"
  - fuel, armband: Move mcp.rsa to /var/lib/opnfv

    JIRA: FUEL-280

    Change-Id: I95559dcafbd179e5b7305dd0f23a7b3d89056888
    Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 7acebb9..a6241f7 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 7acebb9d106278b2718d30d98cc13948e4dc6a3a
+Subproject commit a6241f704f8f8563d7e8fa398f1241fac7031b62