Update git submodules

* Update docs/submodules/armband from branch 'stable/danube'
  - Merge "Update armband documentation for Danube" into stable/danube
  - Update armband documentation for Danube

    JIRA: ARMBAND-243

    Change-Id: If44f1a9f820793c9b04610fd4db7c05a6675f065
    Signed-off-by: Cristina Pauna <cristina.pauna@enea.com>
    (cherry picked from commit b32f9425f4bc80fac6db3f71a17de7be87199e5b)

diff --git a/docs/submodules/armband b/docs/submodules/armband
index 2f5ec26..502b6c7 160000 (submodule)
--- a/docs/submodules/armband
+++ b/docs/submodules/armband
@@ -1 +1 @@
-Subproject commit 2f5ec2617fcbf85d5463deb60860507b1a395db0
+Subproject commit 502b6c79b1a5787e76d2dc4291ef76075a1a06d5