Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Merge "Remove rnc unit test dir as empty"
  - Remove rnc unit test dir as empty

    Change-Id: Id52e49b41f36c58a849c304eed543f8a8465ff9e
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/functest b/docs/submodules/functest
index fece597..15a92a8 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit fece597672ffa6d823e3cb1c23d344171912604d
+Subproject commit 15a92a87526eba65990ed4565dbb4a06ee37c33f