NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic

BugLink: http://bugs.launchpad.net/bugs/1637510

commit 3f807e5a upstream.

The caller of rpc_run_task also gets a reference that must be put.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

fs/nfs/nfs42proc.c

@@ -269,6 +269,7 @@ int nfs42_proc_layoutstats_generic(struct nfs_server *server,
 	task = rpc_run_task(&task_setup);
 	if (IS_ERR(task))
 		return PTR_ERR(task);
+	rpc_put_task(task);
 	return 0;
 }