Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "[fuel] Handle os cacert for baremetal deployments"
  - [fuel] Handle os cacert for baremetal deployments

    Change-Id: I02503772dc5ed59562c2e0aba96280e2cae1da50
    Signed-off-by: Michael Polenchuk <mpolenchuk@mirantis.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 1dd7217..4e9134d 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 1dd7217d50b163834e3b5a3d949af985ad7e9902
+Subproject commit 4e9134d73f7f52f10c637636dea2aa9b84b211a6