scsi: hisi_sas: Remove stray fallthrough annotation

This case statement doesn't fall through any more so remove the fallthrough
annotation.

Link: https://lore.kernel.org/r/20220317075214.GC25237@kiliAcked-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/hisi_sas/hisi_sas_main.c

@@ -442,7 +442,6 @@ void hisi_sas_task_deliver(struct hisi_hba *hisi_hba,
 	case SAS_PROTOCOL_INTERNAL_ABORT:
 		hisi_sas_task_prep_abort(hisi_hba, slot);
 		break;
-	fallthrough;
 	default:
 		return;
 	}