Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Testing live migration using qemu"
  - Testing live migration using qemu

    This patch includes the scripts to execute the live migration using
    qemu and provide the information total time ,VM downtime,setuptime
    once live migration is completed

    Signed-off-by:RajithaY<rajithax.yerrumsetty@intel.com>
    Change-Id: I61380f757f6f3a852fe0a7bc566b10753ce0cc53

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 5abe4fe..54f26bf 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 5abe4fe013a14c528bfb1e0ff4c8bcb9b8817551
+Subproject commit 54f26bfe1cb139545ab86450342c6a7ab520dd83