Update git submodules

Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Create flavor from heat context

    JIRA: YARDSTICK-582

    Create a customizable flavor via heat context. All heat parameters
    are configurable including Core Affinity. The default flavor name
    is XXXX-flavor where XXXX is stackname. Flavor attributes are taken
    from the heat context file. If a flavor attribute is not used it
    takes default attribute value. If flavor name is not specified it
    uses the server name + "-flavor" or stack-name + "-flavor".

    Compute node specific attributes are configurable via "extra_specs"
    attribute. See
    https://docs.openstack.org/admin-guide/compute-flavors.html for
    details.

    Change-Id: If4015970b889b0b95bfa8eba9491ebf31e92f2c7
    Signed-off-by: DanielMartinBuckley <daniel.m.buckley@intel.com>