ACAN_ESP32: Add ACAN_ESP32::end() to stop the controller and remove ISR

[kholk]

Some applications require stopping the controller (at least temporarily) for example when starting the OTA process as, during that, getting any interrupt from the CAN controller may be not desirable, as that could be increasing the likeliness of an OTA failure (and noone wants to end up with a corrupt flash).

The OTA case is just one of the possible examples, anyway.

This was tested on ESP32-S3R8 and S3R2.