Update git submodules

* Update docs/submodules/vswitchperf from branch 'master'
  - ci: Fix typo in MERGE job definition

    Fix of the typo in the name of pylint check function.

    Change-Id: Ie67c95715bd3fda76b2ae47ac8bb48807ffc58c5
    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>

diff --git a/docs/submodules/vswitchperf b/docs/submodules/vswitchperf
index 91e0985..4a4ee67 160000 (submodule)
--- a/docs/submodules/vswitchperf
+++ b/docs/submodules/vswitchperf
@@ -1 +1 @@
-Subproject commit 91e0985be7ca2b2654f89928315431228b7ecc56
+Subproject commit 4a4ee678acca263ac39a67068822f3ffee8ecaf2