Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Add support for VNC to VMs created by ansible"
  - Add support for VNC to VMs created by ansible

    JIRA: YARDSTICK-1017

    Change-Id: I76ca53c12a6791ecbf7f546f9074b16c5f6d215a
    Signed-off-by: John O Loughlin <john.oloughlin@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 8eefd8a..bbd3b02 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 8eefd8ac17fb25c6bcfa219e64a1ad7a81961c40
+Subproject commit bbd3b027bd132568c258f02e36d9cc78c4629dfd