scsi: qla2xxx: Always check the return value of qla24xx_get_isp_stats()

This patch fixes the following Coverity warning:

    CID 361199 (#1 of 1): Unchecked return value (CHECKED_RETURN)
    3. check_return: Calling qla24xx_get_isp_stats without checking return
    value (as is done elsewhere 4 out of 5 times).

Link: https://lore.kernel.org/r/20210320232359.941-7-bvanassche@acm.org
Cc: Quinn Tran <qutran@marvell.com>
Cc: Mike Christie <michael.christie@oracle.com>
Cc: Himanshu Madhani <himanshu.madhani@oracle.com>
Cc: Daniel Wagner <dwagner@suse.de>
Cc: Lee Duncan <lduncan@suse.com>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla2xxx/qla_attr.c

@@ -2864,6 +2864,8 @@ qla2x00_reset_host_stats(struct Scsi_Host *shost)
 	vha->qla_stats.jiffies_at_last_reset = get_jiffies_64();
 
 	if (IS_FWI2_CAPABLE(ha)) {
+		int rval;
+
 		stats = dma_alloc_coherent(&ha->pdev->dev,
 		    sizeof(*stats), &stats_dma, GFP_KERNEL);
 		if (!stats) {
@@ -2873,7 +2875,11 @@ qla2x00_reset_host_stats(struct Scsi_Host *shost)
 		}
 
 		/* reset firmware statistics */
-		qla24xx_get_isp_stats(base_vha, stats, stats_dma, BIT_0);
+		rval = qla24xx_get_isp_stats(base_vha, stats, stats_dma, BIT_0);
+		if (rval != QLA_SUCCESS)
+			ql_log(ql_log_warn, vha, 0x70de,
+			       "Resetting ISP statistics failed: rval = %d\n",
+			       rval);
 
 		dma_free_coherent(&ha->pdev->dev, sizeof(*stats),
 		    stats, stats_dma);