Prepare stable/xena

Change-Id: I6549d5463e7ff3508374eed6494b1a1461194316

.gitreview

@@ -2,3 +2,4 @@
 host=review.opendev.org
 port=29418
 project=x/ironic-staging-drivers.git
+defaultbranch=stable/xena

extra-requirements.txt

@@ -1 +1 @@
-git+https://opendev.org/openstack/ironic#egg=ironic
+git+https://opendev.org/openstack/ironic@stable/xena#egg=ironic

tox.ini

@@ -13,7 +13,7 @@ setenv = VIRTUAL_ENV={envdir}
          LC_ALL=en_US.UTF-8
          TESTS_DIR=./ironic_staging_drivers/tests/unit/
 deps =
-    -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/xena}
     -r{toxinidir}/test-requirements.txt
     -r{toxinidir}/extra-requirements.txt
 commands =
@@ -47,7 +47,7 @@ commands =
 
 [testenv:docs]
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/xena}
   -r{toxinidir}/requirements.txt
   -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -W -b html doc/source doc/build/html
@@ -65,7 +65,7 @@ commands = oslo_debug_helper {posargs}
 [testenv:releasenotes]
 deps =
     reno>=2.5.0 # Apache-2.0
-    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/xena}
     -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -a -E -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html