Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Add arguments to the traffic profile render"
  - Add arguments to the traffic profile render

    In order to render configurable traffic profiles in NSB test cases,
    a new variable is introduced: "extra_arg". The content of
    this variable is added to the VNFD render data, under a key called
    "extra_args".

    This will allow the user to define Jinja templates for traffic profiles.

    E.g.:

      $ cat test_case_definition.yml
      scenarios:
      - type: NSPerf
        traffic_profile: traffic_profile.yml
        extra_args:
          vports: 10

      $ cat traffic_profile.yml
      {% set vports = get(extra_args, 'vports', '0') or 4 %}
      {% for vport in range(vports|int) %}
      uplink_{{vport}}:
        data...
      {% endfor %}

    JIRA: YARDSTICK-946

    Change-Id: Ib3c1f2d89efa012772edf2156e97d5f4742a6b80
    Signed-off-by: Rodolfo Alonso Hernandez <rodolfo.alonso.hernandez@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 9a71438..ec243be 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 9a71438273cefd57c652b6049c697bdf137088c8
+Subproject commit ec243be6d3f3dc3e811e9217209a8c692e3f9c64