Add `axi_dumper` and `axi_dumper_interpret` script.

[micprog]

This module dumps a log from an AXI bus, which can be analyzed with the interpret script for debugging purposes.

[micprog]

I recently came across this which might implement similar functionality: https://github.com/pulp-platform/axi/blob/db457aa8d8996d87ca72486a9b15873042e04d38/src/axi_test.sv#L2195

[thommythomaso]

I recently came across this which might implement similar functionality:

https://github.com/pulp-platform/axi/blob/db457aa8d8996d87ca72486a9b15873042e04d38/src/axi_test.sv#L2195

I like the idea of the axi_dumper overall better. The output is machine-parsable but still human-understandable making this module much more helpful than the classical logger which only creates human-readable output.