crypto: hisilicon/zip - fix the uncleared debug registers

ZIP debug registers aren't cleared even if its driver is removed,
so add a clearing operation when remove driver.

Signed-off-by: Hao Fang <fanghao11@huawei.com>
Signed-off-by: Yang Shen <shenyang39@huawei.com>
Reviewed-by: Zhou Wang <wangzhou1@hisilicon.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>