Get manufacturing header

        Entry:
          AH = 1Bh
          AL = number of record
          DL = drive
          ES:BX -> buffer for manufacturing header (defect list)

        Return:
          CF set on error
            AH = status

        Note:   Manufacturing header format (Defect Map Record format)
                can be found in IBM 70MB, 115MB Fixed Disk Drives
                Technical Reference