Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "Add xtesting project job"
  - Add xtesting project job

    It mainly inherits from functest project jobs.
    xtesting is used everywhere except for project name which has to be
    functest-xtesting from the time being.

    Change-Id: I2c00c01b567b3c65b7acdec5c29b8c839d068366
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 5874207..9ebab7e 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 587420761ffb3ea73ed6f9e791d068e7d3d16d9f
+Subproject commit 9ebab7e0e507dcc99c9bceeb7a2a04201b821730