crypto: hisilicon - Fix issue with wrong number of sg elements after dma map

crypto: hisilicon - Fix issue with wrong number of sg elements after dma map

commit 8debacd60c69beab80736d4af4feca47c2e2bd9e upstream.

We fill the hardware scatter gather list assuming it will need the same
number of elements at the original scatterlist. If an IOMMU is involved,
then it may well need fewer. The return value of dma_map_sg tells us how
many.

Probably never caused visible problems as the hardware won't get to
the elements that are incorrect before it finds enough space.

Fixes: dfed0098ab91 (crypto: hisilicon - add hardware SGL support)
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Zhou Wang <wangzhou1@hisilicon.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>