Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "[fuel] Remove vping_ssh testcase"
  - [fuel] Remove vping_ssh testcase

    Now healthcheck includes vping_ssh, so remove it as a dedicated test
    for verifying patches on gerrit to avoid double checking.

    Change-Id: I4daec677e7d1fdc65997f7a9ab580d5f93ece8a8
    Signed-off-by: Michael Polenchuk <mpolenchuk@mirantis.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 15acdc0..2d3635e 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 15acdc032983c58d3e7de94143e08ad1880bacee
+Subproject commit 2d3635eba79e3176a2da20b851144dcac7fce495