Block live migration works when lvm as backend

Change-Id: I7ac92ca1cd45b4c89d4a155ef08cfe8978c2194f
diff --git a/_modules/runtest/tempest_sections/compute_feature_enabled.py b/_modules/runtest/tempest_sections/compute_feature_enabled.py
index 16366ef..91eb882 100644
--- a/_modules/runtest/tempest_sections/compute_feature_enabled.py
+++ b/_modules/runtest/tempest_sections/compute_feature_enabled.py
@@ -77,7 +77,7 @@
 
         for backend_name,backend in backends.iteritems():
             res = backend['engine']
-            if res == 'ceph':
+            if res == 'lvm':
               return True
         return False