BLE-Controller: RequestRejected not correctly initialized

[kvaellning]

Implementation of RequestRejected soed not pass "self" to the exception initialization, thus leading to an error on construction.

I think it would be good to refactor the errors so that they are using super().__init__(message)-syntax instead of Exception.__init__(message)

[kvaellning]

There's actually a little bit more wrong here, since it uses an error_code argument instead of the more widely used status, which is also referenced in the handling.