mm/secretmem: wire up ->set_page_dirty

Make secretmem up to date with the changes done in commit 0af5737
("mm: require ->set_page_dirty to be explicitly wired up") so that
unconditional call to this method won't cause crashes.

Link: https://lkml.kernel.org/r/20210716063933.31633-1-rppt@kernel.org
Fixes: 0af5737 ("mm: require ->set_page_dirty to be explicitly wired up")
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/secretmem.c

@@ -152,6 +152,7 @@ static void secretmem_freepage(struct page *page)
 }
 
 const struct address_space_operations secretmem_aops = {
+	.set_page_dirty	= __set_page_dirty_no_writeback,
 	.freepage	= secretmem_freepage,
 	.migratepage	= secretmem_migratepage,
 	.isolate_page	= secretmem_isolate_page,