Consoles need to be registered with the "console" device name so that
they are probed by the correct driver. The barebox_register_console()
was already forcing this as it was overwriting the name that was being
passed as argument, but it was failing to provide a unique id for
each new console, so the underlying register_device() would just
return an error when wanting to re-register a device with device name
"console" and id 0.

We remove the unused name parameter from barebox_register_console() as
it is really nowhere used, and also specify DEVICE_ID_DYNAMIC as id,
so that a new unique device id is given to each newly registered
console device.

Signed-off-by: Aleksander Morgado <aleksander@aleksander.es>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>