scsi: hisi_sas: Directly return when running I_T_nexus reset if phy disabled

At hisi_sas_debug_I_T_nexus_reset(), we call sas_phy_reset() to reset a
phy. But if the phy is disabled, sas_phy_reset() will directly return
-ENODEV without issue a phy reset request.

If so, We can directly return -ENODEV to libsas before issue a phy
reset.

Link: https://lore.kernel.org/r/1567774537-20003-4-git-send-email-john.garry@huawei.comSigned-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/hisi_sas/hisi_sas_main.c

@@ -1752,6 +1752,11 @@ static int hisi_sas_debug_I_T_nexus_reset(struct domain_device *device)
 	DECLARE_COMPLETION_ONSTACK(phyreset);
 	int rc, reset_type;
 
+	if (!local_phy->enabled) {
+		sas_put_local_phy(local_phy);
+		return -ENODEV;
+	}
+
 	if (scsi_is_sas_phy_local(local_phy)) {
 		struct asd_sas_phy *sas_phy =
 			sas_ha->sas_phy[local_phy->number];