ubifs: Convert cancel_budget() to take a folio

The one caller already has a folio, so pass it in instead of the page.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>