Update git submodules

* Update docs/submodules/releng/builder from branch 'master'
  to 1e61f2d92db60a5e5dff3cd42417542bb7f7a9fe
  - Merge "Install mvn via lf-maven-install macro"
  - Install mvn via lf-maven-install macro

    The macro is currently our standard way to get Maven onto a system.
    Also add mvn-version variable to allow the template to be overrided
    with a different version by the projects.

    Change-Id: Icc0e945f344ddaddb9b2b865c7ed165fda6fe46d
    Signed-off-by: Thanh Ha <thanh.ha@linuxfoundation.org>

diff --git a/docs/submodules/releng/builder b/docs/submodules/releng/builder
index 529a966d794731128cd14027568e106fc263f710..1e61f2d92db60a5e5dff3cd42417542bb7f7a9fe 160000 (submodule)
--- a/docs/submodules/releng/builder
+++ b/docs/submodules/releng/builder
@@ -1 +1 @@
-Subproject commit 529a966d794731128cd14027568e106fc263f710
+Subproject commit 1e61f2d92db60a5e5dff3cd42417542bb7f7a9fe