sched: reorder signal_struct to remove 8 bytes on 64 bit builds

reorder structure to remove 8 bytes of padding on 64 bit builds
Signed-off-by: NRichard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

include/linux/sched.h

@@ -451,8 +451,8 @@ struct signal_struct {
 	 * - everyone except group_exit_task is stopped during signal delivery
 	 *   of fatal signals, group_exit_task processes the signal.
 	 */
-	struct task_struct	*group_exit_task;
 	int			notify_count;
+	struct task_struct	*group_exit_task;
 
 	/* thread group stop support, overloads group_exit_code too */
 	int			group_stop_count;