Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "dovetail: conditional steps added to fuel-bgpvpn scenario"
  - dovetail: conditional steps added to fuel-bgpvpn scenario

    JIRA: DOVETAIL-432

    1, only run against fuel os-odl_l2-bgpvpn-ha scenario
    this can reduce the CI/pod time resource
    dovetail test cases by now (refstack, ha, ipv6, bgpvpn)
    2, the conditional steps have been successed tested on compass
      to remove the introduce of
      https://gerrit.opnfv.org/gerrit/#/c/34327/
      conditonal steps look more simple and understandable

    Change-Id: I315a789160b8173274b1c1ef916073ced7d5e91b
    Signed-off-by: MatthewLi <matthew.lijun@huawei.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 9df7e82..2c02c55 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 9df7e820f13248c8a703f4cb67e70037211f620b
+Subproject commit 2c02c556fdf29e41f04ad16277efb0c82206cec7