ALSA: mts64: use new parport device model

Modify mts64 driver to use the new parallel port device model.
The advantage of using the device model is that the driver gets binded
to the hardware, we get the feature of hotplug, we can bind/unbind the
driver at runtime.
The changes are in the way the driver gets registered with the parallel
port subsystem and the temporary device to probe mts64 card is removed
and mts64_probe() is used in the probe callback.

Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>