Update git submodules

* Update docs/submodules/releng from branch 'master'
  to fc29e71adbed054b577addba5df7ef269342bca3
  - Fix Functest Xena exclude rules

    https://build.opnfv.org/ci/job/functest-opnfv-functest-tempest-xena-gate/1/console

    Change-Id: Ibabf3664dd4b5c76249be6b7957ab037443d9937
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 5830dd0..fc29e71 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 5830dd08682e4cf574517dcc807a279dfc3088d1
+Subproject commit fc29e71adbed054b577addba5df7ef269342bca3