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/bitrot_test.go

@@ -34,7 +34,7 @@ func testBitrotReaderWriterAlgo(t *testing.T, bitrotAlgo BitrotAlgorithm) {
 	volume := "testvol"
 	filePath := "testfile"
 
-	disk, err := newXLStorage(tmpDir, "")
+	disk, err := newLocalXLStorage(tmpDir)
 	if err != nil {
 		t.Fatal(err)
 	}