Update git submodules

Update git submodules

* Update docs/submodules/sfc from branch 'master'
  - Merge "Remove get_floating_ips()"
  - Remove get_floating_ips()

    get_floating_ips() is non-reusable function, with too much logic
    into it. By using smaller functions, we can compose the same
    functionality and build all tests upon a common set of utilities.

    Using the new functions in functest to retrieve the nova ID for a VNF instance,
    it is possible to use a generic solution at the problem of getting floating
    ips deterministcally to the instances

    Change-Id: Ic7dba908fa6bb343c177fe1a68322d3803ed1707
    Signed-off-by: Juan Vidal <juan.vidal.allende@ericsson.com>