DIET/MINOR: task: reduce struct task size by 8 bytes

Just by reordering the struct task, we could shrink it by 8 bytes from
120 to 112 bytes. A careful reordering allowed each part to be located
closer to the hot parts it's used with, resulting in another performance
increase of about 0.5%.
diff --git a/include/types/task.h b/include/types/task.h
index 405404b..0379a22 100644
--- a/include/types/task.h
+++ b/include/types/task.h
@@ -52,14 +52,14 @@
 
 /* The base for all tasks */
 struct task {
-	struct eb32_node wq;		/* ebtree node used to hold the task in the wait queue */
 	struct eb32_node rq;		/* ebtree node used to hold the task in the run queue */
-	int state;			/* task state : bit field of TASK_* */
-	int expire;			/* next expiration date for this task, in ticks */
+	unsigned short state;		/* task state : bit field of TASK_* */
+	short nice;			/* the task's current nice value from -1024 to +1024 */
 	unsigned int calls;		/* number of times ->process() was called */
 	struct task * (*process)(struct task *t);  /* the function which processes the task */
 	void *context;			/* the task's context */
-	int nice;			/* the task's current nice value from -1024 to +1024 */
+	struct eb32_node wq;		/* ebtree node used to hold the task in the wait queue */
+	int expire;			/* next expiration date for this task, in ticks */
 };
 
 /*