Split the ISOTP support into a separate module

[pschichtel]

Sadly, the ISOTP kernel module support is still no where near getting mainlined and requiring a out of tree kernel module to be loaded during normal build/test execution is kind of awkward.

To improve that situation and to lighten the library for users of the other protocols, it might be a good idea to split out the ISOTP bindings into a separate maven module complete with separate native libraries. This might also be useful in combination with a possible Netty migration (see #20).

[pschichtel]

The situation might be changing sooner than expected when creating this issue. I'm helping out in the testing effort and there might be tries to mainline this within the next few kernel iterations.

[pschichtel]

kernel 5.10 will have the module, though not compiled by default