Update git submodules

* Update docs/submodules/barometer from branch 'stable/danube'
  - docs: update dpdk plugins userguide

    Change-Id: I1b70864588f5fbace0d4eeb2098cbf00b1f63442
    Signed-off-by: Taras Chornyi <tarasx.chornyi@intel.com>

diff --git a/docs/submodules/barometer b/docs/submodules/barometer
index a238e8a..9b39e55 160000 (submodule)
--- a/docs/submodules/barometer
+++ b/docs/submodules/barometer
@@ -1 +1 @@
-Subproject commit a238e8a0ea87790bb38c2dc040adb9dbb80b5bec
+Subproject commit 9b39e554e118a8ad26b4d8966b660d65a003367f