Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Add tempest and rally in functest-features

    SDNVPN also requires these packages.
    It would be refactored in a second step when xtesting is published.

    Change-Id: I069ecf8d60dc0ee1a755d0974913b686f4c7ae61
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index a04bc0f..834c2cd 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit a04bc0fa0a07f825856322bf2ebd359a232057bd
+Subproject commit 834c2cd75b7af478e7456f9fd7a344b5ccf92665