iov_iter: remove setting of page->index

Nothing actually checks page->index, so just remove it.

Link: https://lkml.kernel.org/r/20241216161253.37687-1-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

lib/kunit_iov_iter.c

@@ -63,9 +63,6 @@ static void *__init iov_kunit_create_buffer(struct kunit *test,
 		KUNIT_ASSERT_EQ(test, got, npages);
 	}
 
-	for (int i = 0; i < npages; i++)
-		pages[i]->index = i;
-
 	buffer = vmap(pages, npages, VM_MAP | VM_MAP_PUT_PAGES, PAGE_KERNEL);
         KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buffer);