Update git submodules

Update git submodules

* Update docs/submodules/vswitchperf from branch 'master'
  - dpdk: Support dpdk vhost-user client mode

    Support of vhost-user client mode has been added for both
    OVS and VPP. VSPERF configures vhost-user server mode
    in vswitches by default for backward compatibility.
    Support of vhost-user server mode is deprecated
    in OVS and it can be removed in future releases. Once it will
    happen, we have to change vsperf default behavior to
    usage of vhost-user client ports at vswitch side.

    This patch also fixes processing of boolean configuration
    parameters passed via --test-params option. In the past
    it was not possible to set boolean value to False through
    --test-params option.

    JIRA: VSPERF-517

    Change-Id: I65e341f820edd6c720043a4acc74c5140b05db18
    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>