qla4xxx: fix get_host_stats error propagation

qla4xxx was not always returning -EXYZ error codes when
qla4xxx_get_host_stats failed.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Acked-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/scsi/qla4xxx/ql4_os.c

@@ -1050,6 +1050,7 @@ static int qla4xxx_get_host_stats(struct Scsi_Host *shost, char *buf, int len)
 	if (!ql_iscsi_stats) {
 		ql4_printk(KERN_ERR, ha,
 			   "Unable to allocate memory for iscsi stats\n");
+		ret = -ENOMEM;
 		goto exit_host_stats;
 	}
 
@@ -1058,6 +1059,7 @@ static int qla4xxx_get_host_stats(struct Scsi_Host *shost, char *buf, int len)
 	if (ret != QLA_SUCCESS) {
 		ql4_printk(KERN_ERR, ha,
 			   "Unable to retrieve iscsi stats\n");
+		ret = -EIO;
 		goto exit_host_stats;
 	}
 	host_stats->mactx_frames = le64_to_cpu(ql_iscsi_stats->mac_tx_frames);