Add Surelog/UHDM support as yosys plugin

[mtdudek]

Signed-off-by: Maciej Dudek [email protected]

[kamilrakoczy]

Note: our custom version fork of yosys is still required for UHDM support, but now UHDM frontend is used as a separate plugin to yosys that is dynamically loaded.

[olofk]

Is this still needed with the new flow API?

[kamilrakoczy]

I tried to use the new flow API using fusesoc, but couldn't get it to work. Does the new flow API is already integrated with fusesoc? If yes, are there any examples of correct core file?