Update git submodules

* Update docs/submodules/armband from branch 'master'
  - Update armband documentation for 3.0 release

    Change-Id: I2a71637b67b91cf828bbcf5f6abfbd9c2d6da2eb
    Signed-off-by: Cristina Pauna <cristina.pauna@enea.com>

diff --git a/docs/submodules/armband b/docs/submodules/armband
index d7fdf2f..7dca664 160000 (submodule)
--- a/docs/submodules/armband
+++ b/docs/submodules/armband
@@ -1 +1 @@
-Subproject commit d7fdf2fe5dc992bbd155e9a86b1c02d14be5c3ba
+Subproject commit 7dca6641608ea4085cedaf25107c9f702b4cdeb0