Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Fix Rally output retrieval"
  - Fix Rally output retrieval

    Read stdout until nothing left instead of stopping once the child
    process is terminated.

    Change-Id: I46a2eb93fd614e2e7ff676727eb9dc132c29d03f
    Signed-off-by: Juha Kosonen <juha.kosonen@nokia.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index eb79390..d181f61 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit eb793907cee64bbe2519040559b04d47652cabf0
+Subproject commit d181f61205869adef1b8763feb531cc3df52669f