serial: 8250_exar: Add support for USR298x PCI Modems

serial: 8250_exar: Add support for USR298x PCI Modems

Possibly the last PCI controller-based (i.e. not a soft/winmodem)
dial-up modem one can still buy.

Looks to have a stock XR17C154 PCI UART chip for communication, but for
some reason when provisioning the PCI IDs they swapped the vendor and
subvendor IDs. Otherwise this card would have worked out of the box.

Searching online, some folks seem to not have this issue and others do,
so it is possible only some batches of cards have this error.

Create a new macro to handle the switched IDs and add support here.

Signed-off-by: Andrew Davis <afd@ti.com>
Cc: stable <stable@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230420160209.28221-1-afd@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>