sched/wait: Rename wait_queue_t => wait_queue_entry_t

Rename:

	wait_queue_t		=>	wait_queue_entry_t

'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue",
but in reality it's a queue *entry*. The 'real' queue is the wait queue head,
which had to carry the name.

Start sorting this out by renaming it to 'wait_queue_entry_t'.

This also allows the real structure name 'struct __wait_queue' to
lose its double underscore and become 'struct wait_queue_entry',
which is the more canonical nomenclature for such data types.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index bb66c96..a083f95 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -926,7 +926,7 @@ static bool reorder_tags_to_front(struct list_head *list)
 	return first != NULL;
 }
 
-static int blk_mq_dispatch_wake(wait_queue_t *wait, unsigned mode, int flags,
+static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, int flags,
 				void *key)
 {
 	struct blk_mq_hw_ctx *hctx;