Update git submodules

* Update docs/submodules/fds from branch 'stable/danube'
  - Minor fixes to scenario documentation

    Refer to FDS release notes (instead of APEX
    release notes).

    Change-Id: I2208dffef4d14f54221455fa3b3f6d53905bfe00
    Signed-off-by: Frank Brockners <fbrockne@cisco.com>

diff --git a/docs/submodules/fds b/docs/submodules/fds
index 6111d74..bf5470d 160000 (submodule)
--- a/docs/submodules/fds
+++ b/docs/submodules/fds
@@ -1 +1 @@
-Subproject commit 6111d74dfe937c47f7aa25355e159960a4b5386c
+Subproject commit bf5470d975806f1aa1289dd8456efcbbedc06e3d