Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Sort CentOS build server package to be installed"
  - Sort CentOS build server package to be installed

    Sorts the package list alphabetically so its quicker to read which
    packages are installed.

    Change-Id: I784cfa773aed226301017d5ea64f0485e60c1c4e
    Signed-off-by: Trevor Bramwell <tbramwell@linuxfoundation.org>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 677f6fd..ccda6eb 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 677f6fd87f1d0dfa04017cefa9e5ab5fbbfe8396
+Subproject commit ccda6ebbfd02a489b26614f31d8bb0dfee14ffcb