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/fs/userfaultfd.c b/fs/userfaultfd.c
index 1d622f2..bda64fc 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -81,7 +81,7 @@ struct userfaultfd_unmap_ctx {
 
 struct userfaultfd_wait_queue {
 	struct uffd_msg msg;
-	wait_queue_t wq;
+	wait_queue_entry_t wq;
 	struct userfaultfd_ctx *ctx;
 	bool waken;
 };
@@ -91,7 +91,7 @@ struct userfaultfd_wake_range {
 	unsigned long len;
 };
 
-static int userfaultfd_wake_function(wait_queue_t *wq, unsigned mode,
+static int userfaultfd_wake_function(wait_queue_entry_t *wq, unsigned mode,
 				     int wake_flags, void *key)
 {
 	struct userfaultfd_wake_range *range = key;
@@ -860,7 +860,7 @@ static int userfaultfd_release(struct inode *inode, struct file *file)
 static inline struct userfaultfd_wait_queue *find_userfault_in(
 		wait_queue_head_t *wqh)
 {
-	wait_queue_t *wq;
+	wait_queue_entry_t *wq;
 	struct userfaultfd_wait_queue *uwq;
 
 	VM_BUG_ON(!spin_is_locked(&wqh->lock));
@@ -1747,7 +1747,7 @@ static long userfaultfd_ioctl(struct file *file, unsigned cmd,
 static void userfaultfd_show_fdinfo(struct seq_file *m, struct file *f)
 {
 	struct userfaultfd_ctx *ctx = f->private_data;
-	wait_queue_t *wq;
+	wait_queue_entry_t *wq;
 	struct userfaultfd_wait_queue *uwq;
 	unsigned long pending = 0, total = 0;