Update git submodules

Update git submodules

* Update docs/submodules/vswitchperf from branch 'master'
  - ovs: Change default bridge names

    Default names of OVS bridges used by vsperf were changed
    to avoid accidental collision with 3rd party bridges
    (e.g. linux bridges) already configured at DUT.
    Step driven testcases, which extend existing deployment
    scenarios, were updated to use appropriate configuration
    options instead of hardcoded bridge names.

    JIRA: VSPERF-580

    Change-Id: I8c7eee6d8f6532485ec3a2cc06f26515e665fb7e
    Signed-off-by: Martin Klozik <martin.klozik@tieto.com>
    Reviewed-by: Al Morton <acmorton@att.com>
    Reviewed-by: Christian Trautman <ctrautma@redhat.com>
    Reviewed-by: Sridhar Rao <sridhar.rao@spirent.com>
    Reviewed-by: Richard Elias <richard.elias@tieto.com>