drivers: can: stm32: fix bus-speed

Set the prescaler in register BTR according to the configured bitrate in DTS.
This bug appeared in commit 8b6c1bd4b7a0ae4e1d1b3819d5db728120218c6b

Signed-off-by: Julien D'Ascenzio <julien.dascenzio@paratronic.fr>
1 file changed