crypto: qat - fix use of 'dma_map_single'

DMA_TO_DEVICE synchronisation must be done after the last modification
of the memory region by the software and before it is handed off to
the device.

Signed-off-by: Hui Tang <tanghui20@huawei.com>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>