Update git submodules

* Update docs/submodules/sfc from branch 'master'
  - Update the vnffg templates

    The following tacker patch:

    https://review.openstack.org/#/c/532203/

    changed the syntax of the vnffgd templates

    Change-Id: Ifbf788b02a95c8f45eb97230d3d2da117de158d6
    Signed-off-by: Manuel Buil <mbuil@suse.com>

diff --git a/docs/submodules/sfc b/docs/submodules/sfc
index 575a8c9..242e25c 160000 (submodule)
--- a/docs/submodules/sfc
+++ b/docs/submodules/sfc
@@ -1 +1 @@
-Subproject commit 575a8c98517c587dfdccfad93a6ea119ad689629
+Subproject commit 242e25c987847aa01d4470e96500e085aacc5738