adc.init() takes only bits=12 and ignores it.

[robert-hh]

The implementation of adc.init() accepts for bits only the value 12, and, to make it worse, ignores the supplied value. That does not matter, since the default value is 12. To make adc.init() to meet the documentation, the functions in file modes/pybadc.c can e.g. be changed as follows:

STATIC mp_obj_t adc_init(mp_uint_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
    // parse args
    mp_arg_val_t args[MP_ARRAY_SIZE(pyb_adc_init_args) - 1];
    mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args, MP_ARRAY_SIZE(args), &pyb_adc_init_args[1], args);
    // check the number of bits
    if (args[0].u_int < 9 || args[0].u_int > 12) {
        nlr_raise(mp_obj_new_exception_msg(&mp_type_ValueError, mpexception_value_invalid_arguments));
    }
    pyb_adc_obj_t *self = pos_args[0];
    self->width = args[0].u_int;
    pyb_adc_init(self);
    return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(adc_init_obj, 1, adc_init);