Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Revert "container4nfv: Disable jobs until the project stops changing docker version""
  - Revert "container4nfv: Disable jobs until the project stops changing docker version"

    The project fixed their build script to stop reinstalling docker which downgrades it so the jobs can be enabled back now.

    https://gerrit.opnfv.org/gerrit/#/c/50603/

    This reverts commit c9aac428e09385a5893313a99b6af6652dafd216.

    Change-Id: I529850be56e30e4fdd66929809628b89e3a2ed8f

diff --git a/docs/submodules/releng b/docs/submodules/releng
index a6ad912..0a1fabc 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit a6ad912d1f7ec888a077615f3ae14efa51931dc3
+Subproject commit 0a1fabc0109fda9c7839ef281011909b6f96b10a