USB: serial: ftdi_sio: enable NDI speed hack consistently

USB: serial: ftdi_sio: enable NDI speed hack consistently

The original submission adding support for NDI EMGUIDE Gemini enabled
the existing NDI speed hack which remaps the 19200 line speed to 1.2
Mbps, but this silently fell out during resubmission.

Enable the speed hack also for the new NDI product for consistency. This
will also allow for cleaning up the implementation without resorting to
overengineering.

Link: https://lore.kernel.org/all/YQXPR01MB49870CB7B3075ADDF88A3FD4DF43A@YQXPR01MB4987.CANPRD01.PROD.OUTLOOK.COM/
Link: https://lore.kernel.org/all/YQXPR01MB4987F1E0DA41E689779E6958DF48A@YQXPR01MB4987.CANPRD01.PROD.OUTLOOK.COM/
Cc: Ryan Mann <rmann@ndigital.com>
Signed-off-by: Johan Hovold <johan@kernel.org>