aesio: use bufinfo rather than mp_str_bytes
aesio: use bufinfo rather than mp_str_bytes

In order to accept both `bytes` objects and `bytearray` objects, use a
`bufinfo` construct to retrieve the data rather than
`mp_obj_str_get_data()`.

Signed-off-by: Sean Cross <d7e19930cc1f42c2d0781f4d9e6f1fe5891bf9cf@xobs.io>

adafruit/micropython,adafruit/micropython,adafruit/circuitpython,adafruit/circuitpython,adafruit/micropython,adafruit/circuitpython,adafruit/circuitpython,adafruit/circuitpython,adafruit/micropython,adafruit/circuitpython,adafruit/micropython