scsi: qla2xxx: edif: Reduce disruption due to multiple app start

Multiple app start can trigger a session bounce. Make driver skip over
session teardown if app start is seen more than once.

Link: https://lore.kernel.org/r/20220608115849.16693-4-njavali@marvell.com
Fixes: 7ebb336e ("scsi: qla2xxx: edif: Add start + stop bsgs")
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla2xxx/qla_edif.c

@@ -510,8 +510,7 @@ qla_edif_app_start(scsi_qla_host_t *vha, struct bsg_job *bsg_job)
 		/* mark doorbell as active since an app is now present */
 		vha->e_dbell.db_flags |= EDB_ACTIVE;
 	} else {
-		ql_dbg(ql_dbg_edif, vha, 0x911e, "%s doorbell already active\n",
-		     __func__);
+		goto out;
 	}
 
 	if (N2N_TOPO(vha->hw)) {
@@ -578,6 +577,7 @@ qla_edif_app_start(scsi_qla_host_t *vha, struct bsg_job *bsg_job)
 		     __func__);
 	}
 
+out:
 	appreply.host_support_edif = vha->hw->flags.edif_enabled;
 	appreply.edif_enode_active = vha->pur_cinfo.enode_flags;
 	appreply.edif_edb_active = vha->e_dbell.db_flags;