mt_config_init
static struct mt_config_handle *mt_config_init(dev_info_t *, dev_info_t **,
hdl = mt_config_init(pdip, NULL, flags, major, MT_CONFIG_OP, NULL);
hdl = mt_config_init(dip, dipp, flags, major, MT_UNCONFIG_OP, brevqp);
hdl = mt_config_init(NULL, NULL, flags, child_major, MT_CONFIG_OP,