Update git submodules

* Update docs/submodules/fds from branch 'stable/euphrates'
  - FDS DVR doc - Added east-west traffic diagram

    Change-Id: I107c712a010db22e0afc793de8ea849b638ae219
    Signed-off-by: Lorand Jakab <lojakab@cisco.com>
    (cherry picked from commit f20af6726aef99f3a1fcdc63068fe9f8b89e3479)

diff --git a/docs/submodules/fds b/docs/submodules/fds
index 0a8f200..2542309 160000 (submodule)
--- a/docs/submodules/fds
+++ b/docs/submodules/fds
@@ -1 +1 @@
-Subproject commit 0a8f2003f55ab034079e6a783dd45a22514204bc
+Subproject commit 254230992e3eebdacb4a8ee2587a10e67fcae839