[SCSI] qla2xxx: convert to use the data buffer accessors

- remove the unnecessary map_single path.

- convert to use the new accessors for the sg lists and the
parameters.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index dd076da..18baa5b 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -2426,13 +2426,7 @@
 	struct scsi_cmnd *cmd = sp->cmd;
 
 	if (sp->flags & SRB_DMA_VALID) {
-		if (cmd->use_sg) {
-			dma_unmap_sg(&ha->pdev->dev, cmd->request_buffer,
-			    cmd->use_sg, cmd->sc_data_direction);
-		} else if (cmd->request_bufflen) {
-			dma_unmap_single(&ha->pdev->dev, sp->dma_handle,
-			    cmd->request_bufflen, cmd->sc_data_direction);
-		}
+		scsi_dma_unmap(cmd);
 		sp->flags &= ~SRB_DMA_VALID;
 	}
 	CMD_SP(cmd) = NULL;