Update git submodules

* Update docs/submodules/yardstick from branch 'stable/fraser'
  - Merge "[docs] Updated baremetal instalation instructions" into stable/fraser
  - [docs] Updated baremetal instalation instructions

    JIRA: YARDSTICK-1111

    Change-Id: Iefab24f74c87a0855c2d70090ac34256ffa9200c
    Signed-off-by: Chornyi, TarasX <tarasx.chornyi@intel.com>
    (cherry picked from commit 1c4a5e82aec771aba616879a9a351bade6d6d8d0)

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 73b611a..6af74bd 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 73b611a7683f1812ab8af715662d0b155d6e1e70
+Subproject commit 6af74bdd4c6b8ae9601e8910273b51c347eed97c