Update git submodules

* Update docs/submodules/nfvbench from branch 'stable/euphrates'
  - Move label to opfnv-5.0.0

    Change-Id: If5873bad43c9d69f2087c3fd44180df52fb5fad8
    Signed-off-by: ahothan <ahothan@cisco.com>

diff --git a/docs/submodules/nfvbench b/docs/submodules/nfvbench
index 9e08011..02f70b5 160000 (submodule)
--- a/docs/submodules/nfvbench
+++ b/docs/submodules/nfvbench
@@ -1 +1 @@
-Subproject commit 9e080113aaf787b186ef2dd9017752b022ac0040
+Subproject commit 02f70b50b4895a884c69e38b82149c7ee6a299ce