Update git submodules

* Update docs/submodules/vswitchperf from branch 'master'
  - Merge "CI: Update hugepages configuration"
  - CI: Update hugepages configuration

    Use the number of free hugepages to correctly set hugepages
    configuration. Limit the number of allocated hugepages to
    avoid memory exhaustion.

    Change-Id: Id5239200579f8c43706ffcc769e4963280b9eb2b
    Signed-off-by: Martin Klozik <martinx.klozik@intel.com>

diff --git a/docs/submodules/vswitchperf b/docs/submodules/vswitchperf
index 8ce9980..d5a75d4 160000 (submodule)
--- a/docs/submodules/vswitchperf
+++ b/docs/submodules/vswitchperf
@@ -1 +1 @@
-Subproject commit 8ce9980d09ce0f54c93479e074b9c67a7d59b092
+Subproject commit d5a75d471da124b8e32cd4069fd3faae7bb8161a