Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "container4nfv: adjust arm job timeout"
  - container4nfv: adjust arm job timeout

    Our virtual node is kind of slow in handling all triggered tasks.

    Change-Id: I1b4616561aaaabfe96ef77b4a649a16e888d18c0
    Signed-off-by: Yibo Cai <yibo.cai@arm.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index d01e4c5..2d6b1f1 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit d01e4c56ce1bb8944ec8314670389ffbc4bc8bbc
+Subproject commit 2d6b1f1f71596a239af33b2d474eaff80fb8ffd5