Use the KMEM_CACHE() macro instead of kmem_cache_create() to simplify
the creation of SLAB caches related to delayed refs when the default
values are used.
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>