drivers: can: add syscalls for getting min/max timing values

Add CAN system calls for getting the minimum/maximum timing values
supported by a given CAN controller device driver instance:
- can_get_timing_min()
- can_get_timing_max()
- can_get_timing_min_data()
- can_get_timing_max_data();

Signed-off-by: Henrik Brix Andersen <hebad@vestas.com>