Update CPU wiki page to match supported CPUs

[mithro]

The directory at https://github.com/enjoy-digital/litex/tree/master/litex/soc/cores/cpu has;

• blackparrot
• cv32e40p
• lm32
• microwatt
• minerva
• mor1kx
• picorv32
• rocket
• serv
• vexriscv
• vexriscv_smp
• zynq7000

The wiki page at https://github.com/enjoy-digital/litex/wiki/CPUs only has;

• lm32 -- a LatticeMico32 soft core.
• or1k -- an OpenRISC 1000 soft core (see also Open RISC on Wikipedia).
• picorv32 -- a Small RISC V core by Clifford Wolf, implementing the rv32imc instruction set (or configured subsets)
• vexriscv -- an FPGA Friendly RISC V core by SpinalHDL, implementing the rv32im instruction set (hardware multiply optional)
• minerva -- a CPU core that currently implements the RISC-V RV32I instruction set with its microarchitecture described in plain Python code using the nMigen toolbox.
• rocket -- Rocket Chip, a configurable, fully featured, 64-bit rv64imafdc capable core.

Would be good to update the page a little bit.

[mithro]

@kgugala -- As we have added a lot of these CPUs, we should probably do this work.

[mithro]

I wonder if we should be generating the CPUs page from documentation directly inside the CPU cores Python files?

[mithro]

@enjoy-digital -- What do you think of us putting the documentation the CPU core Python files and then generating a summary page published to the wiki?

[enjoy-digital]

@mithro: Having the documentation in the CPU core python files could be interesting yes but the generating process should be simple (for example a simple script we can run that generates the wiki data to be copy paste). I'd like to avoid using a bot for that since this makes things complicated to maintain.

[scanakci]

FYI, I updated the page to add BlackParrot.