Update git submodules

* Update docs/submodules/armband from branch 'stable/euphrates'
  - Merge "p/fuel: Add opnfv user to libvirt group" into stable/euphrates
  - p/fuel: Add opnfv user to libvirt group

    Change-Id: Ia075a790fce0aeb0d21b20b2775e2cc079311b88
    (cherry picked from commit a7bc88387c4ffa25b12df949a1dce4c090414334)

diff --git a/docs/submodules/armband b/docs/submodules/armband
index c8b6bc1..d79947a 160000 (submodule)
--- a/docs/submodules/armband
+++ b/docs/submodules/armband
@@ -1 +1 @@
-Subproject commit c8b6bc16ff2aeeccd8e4a07a9e1cb8a475fd4748
+Subproject commit d79947a082dd7d342b8572d7f74b690cae605b05