Update git submodules

* Update docs/submodules/sdnvpn from branch 'master'
  - Changing to new docs structure

    Change-Id: I4c15e1635981b2b5fe5473be89b5abab78bfabd5
    Signed-off-by: Nikolas Hermanns <nikolas.hermanns@ericsson.com>

diff --git a/docs/submodules/sdnvpn b/docs/submodules/sdnvpn
index 5960fab..0f8220d 160000 (submodule)
--- a/docs/submodules/sdnvpn
+++ b/docs/submodules/sdnvpn
@@ -1 +1 @@
-Subproject commit 5960fab7230bebbffc439457d5542d086cb3f8af
+Subproject commit 0f8220d5d96cc0a45be00e937c73ab938133e587