Building pulp-toolchain for rv32ic and rv32emc

[kgf]

In theory these are possible, but we did not see a utility for them, I am not surprised these are not included. If you want the smallest possible one EC (ex micro-riscy) is an option, and if you want a 'regular' one (zero-riscy) you have IMC. The other two permutations are AFAIK not supported.

But we are happy to receive contributions