scsi: qla2xxx: Fix the size used in a 'dma_free_coherent()' call

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

[mkp: removed memset() hunk that has already been addressed]

Link: https://lore.kernel.org/r/20200802110721.677707-1-christophe.jaillet@wanadoo.fr
Fixes: 4161cee5 ("[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/qla2xxx/qla_mbx.c

@@ -4964,7 +4964,7 @@ qla25xx_set_els_cmds_supported(scsi_qla_host_t *vha)
 		    "Done %s.\n", __func__);
 	}
 
-	dma_free_coherent(&ha->pdev->dev, DMA_POOL_SIZE,
+	dma_free_coherent(&ha->pdev->dev, ELS_CMD_MAP_SIZE,
 	   els_cmd_map, els_cmd_map_dma);
 
 	return rval;