can: peak_usb: fix missing ctrlmode_ init for every dev

Fixes a missing initialization of ctrlmode and ctrlmode_supported fields,
for all other CAN devices than the first one. This fix only concerns
the PCAN-USB Pro FD dual-channels CAN-FD device made by PEAK-System.

Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>