scsi: qla2xxx: Fix DMA unmap leak

With debug kernel we see following wanings indicating memory leak.

[28809.523959] WARNING: CPU: 3 PID: 6790 at lib/dma-debug.c:978
dma_debug_device_change+0x166/0x1d0
[28809.523964] pci 0000:0c:00.6: DMA-API: device driver has pending DMA
allocations while released from device [count=5]
[28809.523964] One of leaked entries details: [device
address=0x00000002aefe4000] [size=8208 bytes] [mapped with DMA_BIDIRECTIONAL]
[mapped as coherent]

Fix this by unmapping DMA memory.
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla2xxx/qla_bsg.c

@@ -341,6 +341,8 @@ qla2x00_process_els(struct bsg_job *bsg_job)
 		dma_map_sg(&ha->pdev->dev, bsg_job->request_payload.sg_list,
 		bsg_job->request_payload.sg_cnt, DMA_TO_DEVICE);
 	if (!req_sg_cnt) {
+		dma_unmap_sg(&ha->pdev->dev, bsg_job->request_payload.sg_list,
+		    bsg_job->request_payload.sg_cnt, DMA_TO_DEVICE);
 		rval = -ENOMEM;
 		goto done_free_fcport;
 	}
@@ -348,6 +350,8 @@ qla2x00_process_els(struct bsg_job *bsg_job)
 	rsp_sg_cnt = dma_map_sg(&ha->pdev->dev, bsg_job->reply_payload.sg_list,
 		bsg_job->reply_payload.sg_cnt, DMA_FROM_DEVICE);
         if (!rsp_sg_cnt) {
+		dma_unmap_sg(&ha->pdev->dev, bsg_job->reply_payload.sg_list,
+		    bsg_job->reply_payload.sg_cnt, DMA_FROM_DEVICE);
 		rval = -ENOMEM;
 		goto done_free_fcport;
 	}