[$250 bounty] Move CAN ignition hooks and add test

[adeebshihadeh]

CAN ignition lives in board/drivers/can_common.h. This is the last car-specific code in panda and should be moved here.

It should also be possible to fully validate these signals in CI. Assert that the hook doesn't unintentionally trip on all the other cars, etc.

[sshane]

with proper rx checks (counter, checksum, etc.) to reduce chances of overlap between cars

[adeebshihadeh]

with proper rx checks (counter, checksum, etc.) to reduce chances of overlap between cars

Let's do this as a separate issue once this is in.

[sshane]

@ccdunder want to tackle this one?

[aubsw]

@sshane I humbly propose #2131

Lemme know what you think!