Remove Nova v3 XML test skip

Now all of the Nova v3 XML tests have been removed completely, so
this skip is unnecessary.

Change-Id: I7765880f6d0164a3b2310706273b9a330dc36dec
diff --git a/tempest/api/compute/base.py b/tempest/api/compute/base.py
index d1bda83..4014799 100644
--- a/tempest/api/compute/base.py
+++ b/tempest/api/compute/base.py
@@ -312,11 +312,6 @@
     @classmethod
     def setUpClass(cls):
         # By default compute tests do not create network resources
-        if cls._interface == "xml":
-            skip_msg = ("XML interface is being removed from Nova v3. "
-                        "%s will be removed shortly" % cls.__name__)
-            raise cls.skipException(skip_msg)
-
         if not CONF.compute_feature_enabled.api_v3:
             skip_msg = ("%s skipped as nova v3 api is not available" %
                         cls.__name__)