Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "improve tc055 results"
  - improve tc055 results

    Change-Id: Ib1282c75c5f9cdc416bedf5c7a2e2d3f44c737f1
    Signed-off-by: rexlee8776 <limingjiang@huawei.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index a89e7fa..7f46ed4 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit a89e7fa4bf0bf8034daa529dfb70335c2dc6c0e5
+Subproject commit 7f46ed48c51dde7b11502ebac482536048b70177