Disregard healing disks in crawling (#10349)

When crawling never use a disk we know is healing.

Most of the change involves keeping track of the original endpoint on xlStorage
and this also fixes DiskInfo.Endpoint never being populated.

Heal master will print `data-crawl: Disk "http://localhost:9001/data/mindev/data2/xl1" is 
Healing, skipping` once on a cycle (no more often than every 5m).

cmd/storage-rest-server.go

@@ -826,7 +826,7 @@ func registerStorageRESTHandlers(router *mux.Router, endpointZones EndpointZones
 			if !endpoint.IsLocal {
 				continue
 			}
-			storage, err := newXLStorage(endpoint.Path, endpoint.Host)
+			storage, err := newXLStorage(endpoint)
 			if err != nil {
 				if err == errMinDiskSize {
 					logger.Fatal(config.ErrUnableToWriteInBackend(err).Hint(err.Error()), "Unable to initialize backend")