Update git submodules

* Update docs/submodules/releng from branch 'master'
  to f4c43a00986c4fdc1cfdcc3e1d3cdaae9e4aec51
  - Merge "Adding file to build rapid vm qcow2 image"
  - Adding file to build rapid vm qcow2 image

    Adding this yaml file so it will trigger the automatic build of a qcow2
    image to be published on http://artifacts.opnfv.org/samplevnf/images.

    Signed-off-by: Luc Provoost <luc.provoost@intel.com>
    Change-Id: I4956d3ab6be62447284a992832abe185a437ee76

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 14279dd..f4c43a0 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 14279dd573ee974e829c7e4901c3a8bdc388a58a
+Subproject commit f4c43a00986c4fdc1cfdcc3e1d3cdaae9e4aec51