Update git submodules

* Update docs/submodules/yardstick from branch 'master'
  - Merge "Replace neutron get network id with shade."
  - Replace neutron get network id with shade.

    Function get_network_id now uses shade client instead of shade client.
    Removed redundant function: get_port_id.

    JIRA: YARDSTICK-890

    Change-Id: I6081477fee39fa78131187e65daf3d7d3a9e439f
    Signed-off-by: Shobhi Jain <shobhi.jain@intel.com>

diff --git a/docs/submodules/yardstick b/docs/submodules/yardstick
index 3eefef5..7dde4c9 160000 (submodule)
--- a/docs/submodules/yardstick
+++ b/docs/submodules/yardstick
@@ -1 +1 @@
-Subproject commit 3eefef5baaad88b711d0ff639d49378b800a3ad0
+Subproject commit 7dde4c902675ff27143701d067510c58f3bd6207