Don't skip Cinder backup tests based on Swift's availability

In Ia486ffcf3868f9ed04d29208e2a58fda3664d895 cinder backup
tests were incorrectly skipped when Swift is not enabled, to
accomodate the tempest-dsvm-py35 job that runs on Nova change. But
other storage vendors don't run Swift but they still may want to
run these tests.

The correct fix, proposed in I6b85e6d8cb5833bb0e28dae5e406b3bae30eb36c
is to not run c-bak at all for the tempest-dsvm-py35 job if Swift
is not present.

Change-Id: I21c83fe18c1308391afcaadb06784835da89342f
Depends-On: I6b85e6d8cb5833bb0e28dae5e406b3bae30eb36c
diff --git a/tempest/api/volume/admin/test_volumes_backup.py b/tempest/api/volume/admin/test_volumes_backup.py
index 7591612..61d4ba7 100644
--- a/tempest/api/volume/admin/test_volumes_backup.py
+++ b/tempest/api/volume/admin/test_volumes_backup.py
@@ -32,9 +32,6 @@
         super(VolumesBackupsAdminV2Test, cls).skip_checks()
         if not CONF.volume_feature_enabled.backup:
             raise cls.skipException("Cinder backup feature disabled")
-        if not CONF.service_available.swift:
-            skip_msg = ("%s skipped as swift is not available" % cls.__name__)
-            raise cls.skipException(skip_msg)
 
     def _delete_backup(self, backup_id):
         self.admin_backups_client.delete_backup(backup_id)
diff --git a/tempest/api/volume/test_volumes_backup.py b/tempest/api/volume/test_volumes_backup.py
index 03a3774..6dcde08 100644
--- a/tempest/api/volume/test_volumes_backup.py
+++ b/tempest/api/volume/test_volumes_backup.py
@@ -29,9 +29,6 @@
         super(VolumesBackupsV2Test, cls).skip_checks()
         if not CONF.volume_feature_enabled.backup:
             raise cls.skipException("Cinder backup feature disabled")
-        if not CONF.service_available.swift:
-            skip_msg = ("%s skipped as swift is not available" % cls.__name__)
-            raise cls.skipException(skip_msg)
 
     def restore_backup(self, backup_id):
         # Restore a backup