[bug report] ASoC: Intel: mrfld - create separate module for pci part

[Pierre-Louis Bossart]

>>> I would guess that indeed a return 0; is missing, but maybe it's time to
>>> remove this PCI code completely. I can't think of any user of the PCI
>>> parts of this driver.
>>>
>>> Andy, Hans, Mark, Takashi, what do you think?
>>
>> The Edison platform and actually some more based on Intel Merrifield are still
>> alive and on the (second hand) market. But yes, I would rather focus on making
>> SOF working there, but via PCI bus (or with ACPI, ASL code for which one should
>> actually write down, currently it's a device with PCI interface only).
> 
> That said, Pierre, have you been able to setup your Edison to see anything on
> I2S with SOF?

No, I haven't touched my Edison boards since the initial integration
with you and Ferry in 2020. I see that the firmware was updated to 1.8
and the kernel is 5.10+ now, so that should be easier than last time.
We don't really need any change for the driver probe, PCI is just fine,
what's missing is an ACPI recipe to enable audio functionality over the
SSP pins.