io_uring/net: use passed in 'len' in io_recv_buf_select()

len is a pointer to the desired len, use that rather than grab it from
sr->len again. No functional changes as of this patch, but it does
prepare io_recv_buf_select() for getting passed in a value that differs
from sr->len.

Link: https://lore.kernel.org/io-uring/[email protected]
Signed-off-by: Jens Axboe <[email protected]>

Author: axboe

io_uring/net.c

@@ -1076,7 +1076,7 @@ static int io_recv_buf_select(struct io_kiocb *req, struct io_async_msghdr *kmsg
 		}
 
 		if (kmsg->msg.msg_inq > 1)
-			arg.max_len = min_not_zero(sr->len, kmsg->msg.msg_inq);
+			arg.max_len = min_not_zero(*len, kmsg->msg.msg_inq);
 
 		ret = io_buffers_peek(req, &arg);
 		if (unlikely(ret < 0))