Update git submodules

* Update docs/submodules/sfc from branch 'master'
  - Define the timethis function in the sfc repo

    Functest removed the function from their repo, so we need to define it in ours:

    Change-Id: Ica122e57612c38751d8ff810f3ba61b749e867eb
    Signed-off-by: Manuel Buil <mbuil@suse.com>

diff --git a/docs/submodules/sfc b/docs/submodules/sfc
index 242e25c..8346170 160000 (submodule)
--- a/docs/submodules/sfc
+++ b/docs/submodules/sfc
@@ -1 +1 @@
-Subproject commit 242e25c987847aa01d4470e96500e085aacc5738
+Subproject commit 8346170ebffc6407252513a39affa53fc1f45a81