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>

diff --git a/docs/submodules/vswitchperf b/docs/submodules/vswitchperf
index 87f6e48..1cfdb4b 160000 (submodule)
--- a/docs/submodules/vswitchperf
+++ b/docs/submodules/vswitchperf
@@ -1 +1 @@
-Subproject commit 87f6e48ca1b17361955f0d31551b0c6360028688
+Subproject commit 1cfdb4bfbdd1ee02e6ab8bce691084d5319d5410