Use newly exposed BLE constants

Newly merged pull request to `adafruit_ble` (https://github.com/adafruit/Adafruit_CircuitPython_BLE/pull/154) exposes `MANUFACTURING_DATA_ADT` and `ADAFRUIT_COMPANY_ID`, so they are no longer needed to be defined by this library.  They should instead be imported from `adafruit_ble` once those changes are released.