Update git submodules

* Update docs/submodules/sfc from branch 'master'
  - Take into account last Functest config updates

    It follows the next changes (Functest) which renamed the related
    config entry [1].

    [1] https://gerrit.opnfv.org/gerrit/#/c/51283/5/functest/ci/config_functest.yaml

    Change-Id: Ieae5baff13bb70aa35b01c2358ab4865cdb9dfb0
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/sfc b/docs/submodules/sfc
index ee6b39a..e55afb9 160000 (submodule)
--- a/docs/submodules/sfc
+++ b/docs/submodules/sfc
@@ -1 +1 @@
-Subproject commit ee6b39aceec72cde4b758b6bd5ea7bab605fb8ed
+Subproject commit e55afb91505df4832e9d54fc794e97fdda35b7df