Update git submodules

* Update docs/submodules/sfc from branch 'master'
  - Added parentheses in 'openstack_utils.py' line#476

    Parentheses were added around the arguments in line#476
    for proper formatting the Exception message in line#475

    Change-Id: I3b2233aea10ff5afd23da00a837b976456274a51
    Signed-off-by: Venkata Harshavardhan Reddy Allu <venkataharshavardhan_ven@srmuniv.edu.in>

diff --git a/docs/submodules/sfc b/docs/submodules/sfc
index e5d90a8..8d4bbbb 160000 (submodule)
--- a/docs/submodules/sfc
+++ b/docs/submodules/sfc
@@ -1 +1 @@
-Subproject commit e5d90a850366caa01f8a34563a5303c6cfe5f011
+Subproject commit 8d4bbbb2d00726f0308311e61127fe53ac595322