As Andrzej suggested, use EP5_BUF_SIZE macro to replace the other three
places of 4096 in cx231xx with EP5_BUF_SIZE.
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Suggested-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>