mm: remove nth_page()

Now that all users are gone, let's remove it.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: David Hildenbrand <[e-mail]>
Reviewed-by: Lorenzo Stoakes <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

include/linux/mm.h

···
 
 #if defined(CONFIG_SPARSEMEM) && !defined(CONFIG_SPARSEMEM_VMEMMAP)
 bool page_range_contiguous(const struct page *page, unsigned long nr_pages);
-#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
 #else
-#define nth_page(page,n) ((page) + (n))
 static inline bool page_range_contiguous(const struct page *page,
 		unsigned long nr_pages)
 {

tools/testing/scatterlist/linux/mm.h

···
 
 #define page_to_pfn(page) ((unsigned long)(page) / PAGE_SIZE)
 #define pfn_to_page(pfn) (void *)((pfn) * PAGE_SIZE)
-#define nth_page(page,n) pfn_to_page(page_to_pfn((page)) + (n))
 
 #define __min(t1, t2, min1, min2, x, y) ({              \
 	t1 min1 = (x);                                  \