Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Clone Releng with submodules to include jjb"
  - Clone Releng with submodules to include jjb

    Needed for JJB verify and Merge to work.
    These jobs are going away, but first we need to get a verified +1
    from jenkins

    Also remove  releng-comment-jjb its unused

    Change-Id: Ice2ad625f87f1d9c841979ede4bb1943110691c8
    Signed-off-by: Aric Gardner <agardner@linuxfoundation.org>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 7d99dc0..68a3a74 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 7d99dc08b6913d2a0202b092c184c364872b891e
+Subproject commit 68a3a74f28122922978c8042be6d799678fdc976