Update git submodules

* Update docs/submodules/vswitchperf from branch 'master'
  - bugfix: Define _EXECUTED_PIDS in config file

    Add definition of internal _EXECUTED_PIDS list into generic
    configuration file.

    JIRA: VSPERF-556

    Change-Id: I6c237cb563c0a37bf806561d1f841587796399b8
    Signed-off-by: Martin Klozik <martinx.klozik@intel.com>

diff --git a/docs/submodules/vswitchperf b/docs/submodules/vswitchperf
index c870b4c..52c154c 160000 (submodule)
--- a/docs/submodules/vswitchperf
+++ b/docs/submodules/vswitchperf
@@ -1 +1 @@
-Subproject commit c870b4c5e4360008e17dda745fc9ce11b212f702
+Subproject commit 52c154c463705b51c54d639026093ecd80c9a6b4