Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Config physical network when creating tempest net"
  - Config physical network when creating tempest net

    When the network_type is vlan, physical_network and
    segmentation_id could be configured.
    This also supports to config physical network when creating
    rally net.

    Change-Id: I9770968537c1509c5712eada66925a4bf8f6678c
    Signed-off-by: Linda Wang <wangwulin@huawei.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index ef1a20e..171a354 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit ef1a20eb5cee095d6f8d15fba0ae533e9e4b9730
+Subproject commit 171a354252112e6b1590358120c818cc7ce20c3b