Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Adding latency test for vfw"
  - Adding latency test for vfw

    Change-Id: Ibed8bf057a76f55a9e4cc5c55a104350e43a2a6e
    Signed-off-by: Deepak S <deepak.s@linux.intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index fbe40b8..050a745 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit fbe40b8bdd439e318147d2f1e386357ec941875e
+Subproject commit 050a7452ef96c2a5d887207587436fc61e7d24cd