The only caller already has a folio, so push the folio->page conversion
down a level.

Link: https://lkml.kernel.org/r/20220617175020.717127-21-willy@infradead.org


Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>