Update git submodules

* Update docs/submodules/apex from branch 'stable/euphrates'
  - Fix releasenotes label and include paths for docs

    Change-Id: I50a8f35165954b9b4bdf62864055ad475843c179
    Signed-off-by: Trevor Bramwell <tbramwell@linuxfoundation.org>

diff --git a/docs/submodules/apex b/docs/submodules/apex
index 0c7e218..ebff3ec 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit 0c7e2184e76eaedc5b2e4ccfc20a6e15f7579164
+Subproject commit ebff3ecd633a5df4ab3c995dce8a939762a88904