Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "operation_general: fix logging to use %s"
  - operation_general: fix logging to use %s

    Change-Id: I1b37cbf07e8858ca3e75bb74c57fe84485ff4989
    Signed-off-by: Ross Brattain <ross.b.brattain@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 07249e0..942b411 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 07249e010dd9837d63f3090f1eac0fc6763b968f
+Subproject commit 942b41170ebb412cef1ccc0c134ea8984e82171d