aio: fix wrong comment in aio_complete()

ctx->ctx_lock should be ctx->completion_lock.

Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/aio.c b/fs/aio.c
index a8ecc83..9b5ca11 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -625,7 +625,7 @@
 
 	/*
 	 * Add a completion event to the ring buffer. Must be done holding
-	 * ctx->ctx_lock to prevent other code from messing with the tail
+	 * ctx->completion_lock to prevent other code from messing with the tail
 	 * pointer since we might be called from irq context.
 	 */
 	spin_lock_irqsave(&ctx->completion_lock, flags);