fix memory leak in DIR for copy-job

fix memory leak in DIR for copy-job

- 127.0.0.1-dir: smartall.c:409-0 Orphaned buffer: 127.0.0.1-dir
  24 bytes at 7fdd44010fd8 from  mac_sql.c:714
- dlist::remove() don't free the item that is removed, you have to
  delete it yourself

127.0.0.1-dir: mac_sql.c:527-0 regex-sel-pattern=RestartJob
127.0.0.1-dir: mac_sql.c:530-0 get name query1=SELECT DISTINCT Job.Name from Job,Pool WHERE Pool.Name='Default' AND Job.PoolId=Pool.PoolId
127.0.0.1-dir: mac_sql.c:537-0 query1 returned 2 names
127.0.0.1-dir: mac_sql.c:561-0 get name Item=ContinuousJob 7fdd44010fd8 7fdd440276d8
127.0.0.1-dir: mac_sql.c:557-0 Remove item ContinuousJob
127.0.0.1-dir: mac_sql.c:561-0 get name Item=RestartJob 7fdd44011118 7fdd4404a478
127.0.0.1-dir: mac_sql.c:589-0 Got Job: RestartJob
127.0.0.1-dir: mac_sql.c:591-0 get id from name query2=SELECT DISTINCT Job.JobId,Job.StartTime FROM Job,Pool WHERE Job.Name='RestartJob' AND Pool.Name='Default' AND Job.PoolId=Pool.PoolId ORDER by Job.StartTime
127.0.0.1-dir: mac_sql.c:604-0 Count=2 Jobids=1,4
127.0.0.1-dir: mac_sql.c:606-0 Free 7fdd44011118 7fdd4404a478 RestartJob
127.0.0.1-dir: dlist.c:327-0 Destroy head=7fdd44011118
127.0.0.1-dir: dlist.c:330-0 Destroy free n=7fdd44011118 ni=0

127.0.0.1-dir: smartall.c:409-0 Orphaned buffer: 127.0.0.1-dir 24 bytes at 7fdd44010fd8 from mac_sql.c:714