mm: remove lru_to_page()

The last user was removed over a year ago; remove the definition.

Link: https://lkml.kernel.org/r/20240227174254.710559-16-willy@infradead.orgSigned-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

include/linux/mm.h

@@ -227,7 +227,6 @@ int overcommit_policy_handler(struct ctl_table *, int, void *, size_t *,
 /* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
 #define PAGE_ALIGNED(addr)	IS_ALIGNED((unsigned long)(addr), PAGE_SIZE)
 
-#define lru_to_page(head) (list_entry((head)->prev, struct page, lru))
 static inline struct folio *lru_to_folio(struct list_head *head)
 {
 	return list_entry((head)->prev, struct folio, lru);