Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Add ACL sample config file"
  - Add ACL sample config file

    The acl_rules.yaml is unused, so renamed it to sample config.
    Updated the config with example of possible ACL configuration.

    JIRA: YARDSTICK-1304

    Change-Id: If0537cf55f4c96f57844caed5bf1c9050647e0d5
    Signed-off-by: Mytnyk, Volodymyr <volodymyrx.mytnyk@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 2a28604..70e0f37 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 2a286049b340801cff37329921f2ecca8a33c3fa
+Subproject commit 70e0f379bffcd0837fea69bdac5e9148270e257b