media: cxusb: restore RC_MAP for MyGica T230

Commit f8585ce6 ("[media] dvb-usb-cxusb: Geniatech T230C support")
sneaked in an unrelated change for the older T230 (not C) model.

As the commit was reverted this change was reverted too,
although likely correct.

Fixes: f8585ce6 ("[media] dvb-usb-cxusb: Geniatech T230C support")
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>