Update git submodules

* Update docs/submodules/sfc from branch 'master'
  - Merge "Avoid race conditions"
  - Avoid race conditions

    Sometimes the port pair group gets created before port pair was
    committed in openstack. Before creating the port pair group, we check
    that the port pair is already listed by openstack

    Change-Id: Icfd23521859fc5d4e6bb6745be80f79bf9e31a0c
    Signed-off-by: Manuel Buil <mbuil@suse.com>

diff --git a/docs/submodules/sfc b/docs/submodules/sfc
index 0eb8ab4..584dd94 160000 (submodule)
--- a/docs/submodules/sfc
+++ b/docs/submodules/sfc
@@ -1 +1 @@
-Subproject commit 0eb8ab44ae9192f08026f659bc40cddb48703afb
+Subproject commit 584dd944d267150f0071e9e13a7dff2a8123ef61