Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "[Functest] Exclude vnf tests for virtual deployments"
  - [Functest] Exclude vnf tests for virtual deployments

    VNF test cases take long time when executed in
    virtual deployments, mainly due to the resources
    assigned to the virtual hosts.

    Change-Id: Id0591e6217515b04fe163488a89667ac66c06cdd
    Signed-off-by: JoseLausuch <lausso@Joses-iMac.local>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 05b71c3..a9bac24 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 05b71c3faa930789f6ed603633875647f6a33ee8
+Subproject commit a9bac248658d45c2fc18c9ba44dac3adbd79b456