Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "jjb/releng: support multi arch compass images"
  - jjb/releng: support multi arch compass images

    Change-Id: I9f6a287727d36266207fb2821127ac142952f67d
    Signed-off-by: Yibo Cai <yibo.cai@arm.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index e20fc53..a5ada7e 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit e20fc538ed2fd242d0db1518289e6be4a2829681
+Subproject commit a5ada7e9390cb87b858a29370a7dc09507c07c2e