vhost: remove the second argument of k[un]map_atomic()

Signed-off-by: Cong Wang <amwang@redhat.com>

drivers/vhost/vhost.c

@@ -937,9 +937,9 @@ static int set_bit_to_user(int nr, void __user *addr)
 	if (r < 0)
 		return r;
 	BUG_ON(r != 1);
-	base = kmap_atomic(page, KM_USER0);
+	base = kmap_atomic(page);
 	set_bit(bit, base);
-	kunmap_atomic(base, KM_USER0);
+	kunmap_atomic(base);
 	set_page_dirty_lock(page);
 	put_page(page);
 	return 0;