Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Remove all references to /home/opnfv/repos/functest"
  - Remove all references to /home/opnfv/repos/functest

    It also removes relative (and incomplete) references which could be
    defined in modules instead of this global configuration.

    Change-Id: Ie20dc3547e49b6224aa8100cd380d37b87ece5a9
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index e7ab535..51899de 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit e7ab53553d719b0fb35b4a74cd0bbc9572c7a48d
+Subproject commit 51899de7927bbf6be76639508ae2970046add625