truncate: Add invalidate_complete_folio2()

Convert invalidate_complete_page2() to invalidate_complete_folio2().
Use filemap_free_folio() to free the page instead of calling ->freepage
manually.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
diff --git a/mm/filemap.c b/mm/filemap.c
index 4c39e09..72ea824 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -229,8 +229,7 @@ void __filemap_remove_folio(struct folio *folio, void *shadow)
 	page_cache_delete(mapping, folio, shadow);
 }
 
-static void filemap_free_folio(struct address_space *mapping,
-				struct folio *folio)
+void filemap_free_folio(struct address_space *mapping, struct folio *folio)
 {
 	void (*freepage)(struct page *);