crypto: hisilicon/hpre - fix dma unmap sequence

[ Upstream commit 982fd1a7 ]

Perform DMA unmapping operations before processing data.
Otherwise, there may be unsynchronized data accessed by
the CPU when the SWIOTLB is enabled.

Signed-off-by: Zhiqi Song <songzhiqi1@huawei.com>
Signed-off-by: Chenghai Huang <huangchenghai2@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>