fs: get rid of the res2 iocb->ki_complete argument

The second argument was only used by the USB gadget code, yet everyone
pays the overhead of passing a zero to be passed into aio, where it
ends up being part of the aio res2 value.

Now that everybody is passing in zero, kill off the extra argument.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 11404f8..e6039f2 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -687,7 +687,7 @@ static void fuse_aio_complete(struct fuse_io_priv *io, int err, ssize_t pos)
 			spin_unlock(&fi->lock);
 		}
 
-		io->iocb->ki_complete(io->iocb, res, 0);
+		io->iocb->ki_complete(io->iocb, res);
 	}
 
 	kref_put(&io->refcnt, fuse_io_release);