Update git submodules

* Update docs/submodules/fds from branch 'stable/danube'
  - Updated release notes for Danube 3.0

    Change-Id: Ifd4219edcb10bd367b500e7316418e1b1461b887
    Signed-off-by: juraj.linkes <jlinkes@cisco.com>

diff --git a/docs/submodules/fds b/docs/submodules/fds
index db7fee4..620160c 160000 (submodule)
--- a/docs/submodules/fds
+++ b/docs/submodules/fds
@@ -1 +1 @@
-Subproject commit db7fee452f166d7e4177bd08cb47ba6327474749
+Subproject commit 620160c9312181527f9911e89d888af05f4e1f67