Update git submodules

* Update docs/submodules/releng from branch 'master'
  - functest: Create jobs for Euphrates

    This change switches jobs to euphrates and removes danube jobs.

    Change-Id: I9e53c595886b6214927c10c380a898e3c7510c7b
    Signed-off-by: Fatih Degirmenci <fatih.degirmenci@ericsson.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index a4c213d..d0449db 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit a4c213d48688fba421c0e380c0f96978589af501
+Subproject commit d0449dba1281968d9ba9343d812057bd7e5758dc