Update git submodules

Update git submodules

* Update docs/submodules/vswitchperf from branch 'master'
  - vpp: Multiqueue support for VPP

    VPP class was updated to configure RX queues of VPP interfaces
    based on VSWITCH_DPDK_MULTI_QUEUES value.

    Change-Id: I855dbaef86cf935b2639976e8b1757eb1af4e9ac
    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>