Remove extra swift delete_object call

This only tries to delete the manifest once when deleting an image
stored (chunked) in swift. Fixes bug 903768.

(cherry picked from commit c062423)

Change-Id: I65b8f3389e9965a111c4e774f4d1b6f7bbe71a9b

glance/store/swift.py

@@ -453,7 +453,9 @@ def delete(self, location):
                     # be hogging up network or file I/O here...
                     swift_conn.delete_object(obj_container, segment['name'])
 
-            swift_conn.delete_object(loc.container, loc.obj)
+            else:
+                swift_conn.delete_object(loc.container, loc.obj)
+
         except swift_client.ClientException, e:
             if e.http_status == httplib.NOT_FOUND:
                 uri = location.get_store_uri()