Update git submodules

* Update docs/submodules/container4nfv from branch 'stable/fraser'
  - modify release-notes

    Change-Id: I7041c004ca94705e1ac8cb03b6a06a906db0be35
    Signed-off-by: Xuan Jia <jason.jiaxuan@gmail.com>

diff --git a/docs/submodules/container4nfv b/docs/submodules/container4nfv
index 84ce45c..38d0ffe 160000 (submodule)
--- a/docs/submodules/container4nfv
+++ b/docs/submodules/container4nfv
@@ -1 +1 @@
-Subproject commit 84ce45c8bf6e03f0373d9c46e0a8b7e0b3faa605
+Subproject commit 38d0ffe507a137167ffdbac860de5c1a738e81a8