Update git submodules

* Update docs/submodules/sdnvpn from branch 'master'
  - os-odl-bgpvpn scenario for xci deployment

    This includes scenario os-odl-bgpvpn scenario specific configuration
    files to make XCI to install Openstack (master and stable/pike) with
    OpenDaylight configured as a BGP speaker.
    XCI would automatically checkout sdnvpn repo and use scenarios
    directory for the configuration during its execution time.

    Change-Id: Ic86fcb171c8e97f7d3c3fb649ab0fb00368e6c6d
    Signed-off-by: Periyasamy Palanisamy <periyasamy.palanisamy@ericsson.com>

diff --git a/docs/submodules/sdnvpn b/docs/submodules/sdnvpn
index fbfb251..56791ea 160000 (submodule)
--- a/docs/submodules/sdnvpn
+++ b/docs/submodules/sdnvpn
@@ -1 +1 @@
-Subproject commit fbfb2513a8bc4f82ba2f5e69e64da659716cfb2d
+Subproject commit 56791ea2dc5bcd0ba2d1811753dbbb5934fd8a92