pnet_get_station_name function need

[SupermanOfHeiLinPu]

After the profinet controller assigns the profinet device name, the name obtained through pnet_cfg_t is incorrect, so an interface is needed to obtain the profinet device name.

[pyhys]

The name given in pnet_cfg_t is the device name used at first startup, or after factory reset.

I think maybe we could add a callback at IP and station name changes, to inform the application.