Update git submodules

* Update docs/submodules/compass4nfv from branch 'stable/euphrates'
  - Config dpdk and ovs

    switch dpdk interface driver and bring
    up corresponding ovs bridges.

    Change-Id: I07bd9b332978482507711cfbd8ad29802a8b1a8c
    Signed-off-by: Harry Huang <huangxiangyu5@huawei.com>
    (cherry picked from commit 849d51833bdb16e8f04370270cd3e082ad9db928)

diff --git a/docs/submodules/compass4nfv b/docs/submodules/compass4nfv
index 70401f1..91c5b7e 160000 (submodule)
--- a/docs/submodules/compass4nfv
+++ b/docs/submodules/compass4nfv
@@ -1 +1 @@
-Subproject commit 70401f149efee11604487976e67f49f97217f6bd
+Subproject commit 91c5b7efc59bcf9a6482c764f4d7d2e473b8f6d2