Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Increase rounding digits in IXIA RFC2544"
  - Increase rounding digits in IXIA RFC2544

    Increase rounding digits in IXIA RFC2544 for:
      - Drop percentage: 6 digits
      - Rate: 5 digits, both for fps and % line rate.

    JIRA: YARDSTICK-1338

    Change-Id: Iae6e49dd3d15035452f28976af0b16222fa8e23c
    Signed-off-by: Rodolfo Alonso Hernandez <rodolfo.alonso.hernandez@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index ead6f55..61d471c 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit ead6f55e0cef44a601902f653f5c0f304a3dc01a
+Subproject commit 61d471c367ff61cbac080bd1708decf1b36ad167