sched/wait: Standardize 'struct wait_bit_queue' wait-queue entry field name

Rename 'struct wait_bit_queue::wait' to ::wq_entry, to more clearly
name it as a wait-queue entry.

Propagate it to a couple of usage sites where the wait-bit-queue internals
are exposed.

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>

fs/jbd2/journal.c

@@ -2579,10 +2579,10 @@ restart:
 		wait_queue_head_t *wq;
 		DEFINE_WAIT_BIT(wait, &jinode->i_flags, __JI_COMMIT_RUNNING);
 		wq = bit_waitqueue(&jinode->i_flags, __JI_COMMIT_RUNNING);
-		prepare_to_wait(wq, &wait.wait, TASK_UNINTERRUPTIBLE);
+		prepare_to_wait(wq, &wait.wq_entry, TASK_UNINTERRUPTIBLE);
 		spin_unlock(&journal->j_list_lock);
 		schedule();
-		finish_wait(wq, &wait.wait);
+		finish_wait(wq, &wait.wq_entry);
 		goto restart;
 	}