scsi: aic94xx: Add missing check for dma_map_single()

Add check for dma_map_single() and return error if it fails in order to
avoid invalid DMA address.

Fixes: 2908d778 ("[SCSI] aic94xx: new driver")
Link: https://lore.kernel.org/r/20230128110832.6792-1-jiasheng@iscas.ac.cn


Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>