scsi: qla4xxx: Fix an error handling path in 'qla4xxx_get_host_stats()'

Update the size used in 'dma_free_coherent()' in order to match the one
used in the corresponding 'dma_alloc_coherent()'.

Link: https://lore.kernel.org/r/20200802101527.676054-1-christophe.jaillet@wanadoo.fr
Fixes: 4161cee52d ("[SCSI] qla4xxx: Add host statistics support")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla4xxx/ql4_os.c

@@ -1254,7 +1254,7 @@ static int qla4xxx_get_host_stats(struct Scsi_Host *shost, char *buf, int len)
 			le64_to_cpu(ql_iscsi_stats->iscsi_sequence_error);
 exit_host_stats:
 	if (ql_iscsi_stats)
-		dma_free_coherent(&ha->pdev->dev, host_stats_size,
+		dma_free_coherent(&ha->pdev->dev, stats_size,
 				  ql_iscsi_stats, iscsi_stats_dma);
 
 	ql4_printk(KERN_INFO, ha, "%s: Get host stats done\n",