Update git submodules

Update git submodules

* Update docs/submodules/vswitchperf from branch 'master'
  - ci: Use log scale for B2B graphs

    Graph configuration for B2B was modified to show correct y axis
    tittle and to use log scale.

    Change-Id: I7ac75ca803f93be28d89a4504e046b1119d341e1
    Signed-off-by: Martin Klozik <martinx.klozik@intel.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: Trevor Cooper <trevor.cooper@intel.com>