[dv,cosim] Implement internal interrupts in co-sim

[GregAC]

Add support to cosim for internal interrupts (documented at https://ibex-core.readthedocs.io/en/latest/03_reference/exception_interrupts.html#internal-interrupts)

estimate 8
remaining 2022-10-06 4
remaining 2022-10-14 2
remaining 2022-11-01 1

[ctopal]

remaining 2022-10-14 2

[GregAC]

@GregAC to add write suppression on ECC failures on load to co-sim environment

[GregAC]

I have a set of commits on top of Canberk's work in #1811 but no PR yet. Once that is merged this will be complete.

[GregAC]

Completed by #1907