wait: collapse into one type definition

index bd68819..d5ba4c6 100644
@@ -32,11 +32,10 @@ struct wait_bit_queue {
     wait_queue_t        wait;
 };
 
-struct __wait_queue_head {
+typedef struct {
     spinlock_t        lock;
     struct list_head    task_list;
-};
-typedef struct __wait_queue_head wait_queue_head_t;
+} wait_queue_head_t;
 
 struct task_struct;