getDisksInfo: Attribute failed disks to correct endpoint (#10360)

If DiskInfo calls failed the information returned was used anyway 
resulting in no endpoint being set.

This would make the drive be attributed to the local system since 
`disk.Endpoint == disk.DrivePath` in that case.

Instead, if the call fails record the endpoint and the error only.

cmd/admin-handlers.go

@@ -1499,6 +1499,9 @@ func (a adminAPIHandlers) ServerInfoHandler(w http.ResponseWriter, r *http.Reque
 	}
 	// add all the disks local to this server.
 	for _, disk := range storageInfo.Disks {
+		if disk.DrivePath == "" && disk.Endpoint == "" {
+			continue
+		}
 		if disk.Endpoint == disk.DrivePath {
 			servers[len(servers)-1].Disks = append(servers[len(servers)-1].Disks, disk)
 		}

cmd/erasure.go

@@ -146,6 +146,11 @@ func getDisksInfo(disks []StorageAPI, endpoints []string) (disksInfo []madmin.Di
 					ctx := logger.SetReqInfo(GlobalContext, reqInfo)
 					logger.LogIf(ctx, err)
 				}
+				disksInfo[index] = madmin.Disk{
+					State:    diskErrToDriveState(err),
+					Endpoint: endpoints[index],
+				}
+				return err
 			}
 			di := madmin.Disk{
 				Endpoint:       endpoints[index],