iov_iter: move iter_ubuf check inside restore WARN

io_uring is using iter_ubuf types for single vector requests. We expect
state restore may happen for this type now, and it is already handled
correctly, so suppress the warning.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Christoph Hellwig <hch@lst.de>

lib/iov_iter.c

@@ -1902,8 +1902,8 @@ int import_ubuf(int rw, void __user *buf, size_t len, struct iov_iter *i)
  */
 void iov_iter_restore(struct iov_iter *i, struct iov_iter_state *state)
 {
-	if (WARN_ON_ONCE(!iov_iter_is_bvec(i) && !iter_is_iovec(i)) &&
-			 !iov_iter_is_kvec(i) && !iter_is_ubuf(i))
+	if (WARN_ON_ONCE(!iov_iter_is_bvec(i) && !iter_is_iovec(i) &&
+			 !iter_is_ubuf(i)) && !iov_iter_is_kvec(i))
 		return;
 	i->iov_offset = state->iov_offset;
 	i->count = state->count;