Update git submodules

* Update docs/submodules/sfc from branch 'master'
  - Update entry_point to conform with Xtesting

    Functest is being updated to Xtesting 0.60 which leverages on
    stevedore [1].

    [1] https://docs.openstack.org/stevedore/latest/

    Change-Id: I09382b458929fabd21b5351b9d84b0d73fe2657e
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/sfc b/docs/submodules/sfc
index dacf2b5..9ff67de 160000 (submodule)
--- a/docs/submodules/sfc
+++ b/docs/submodules/sfc
@@ -1 +1 @@
-Subproject commit dacf2b5d84226f3844dfc0b949ef81446d4c353a
+Subproject commit 9ff67de3c3857c7d3bc075133e0da822e455880a