Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Switch yamllint job to only run against new files"
  - Switch yamllint job to only run against new files

    Intead of yamllint all files at once yamllint will only run against new
    or modified yaml files.

    Change-Id: I10b951427966409e15fb773b959adbd780497bad
    Signed-off-by: Trevor Bramwell <tbramwell@linuxfoundation.org>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 500717b..31ce289 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 500717bd3b46eb4855428eead7894141bf6d6a15
+Subproject commit 31ce289ac966e8ed104a431e659c1a98dcb54de6