setups/osflow/synthesis: recent versions of yosys need command 'read_verilog'

[umarcor]

Close #245

Refs:

• Recent version of yosys need read_verilog command im-tomu/fomu-workshop#600
• Project with mixed VHDL and Verilog generate wrong cell for PLL  YosysHQ/yosys#3137
• Regression following 'Use "read" command' change YosysHQ/yosys#3109

[stnolting]

Awesome! Thanks for fixing!

[umarcor]

Note that Windows CI is still broken. That is a different issue. I think some dependency of nextpnr is missing, so it crashes. I'm looking into it.

[stnolting]

Note that Windows CI is still broken. That is a different issue. I think some dependency of nextpnr is missing, so it crashes.

I have notices that, but that issue has not yet reached "urgent level" on my to-do stack 😉

I'm looking into it.

Thanks!

[umarcor]

I have notices that, but that issue has not yet reached "urgent level" on my to-do stack 😉

Anyway, it's fixed now 😄. nextpnr-ecp5 is crashing arbitrarily (orangecrab and/or ulx3s), however, that is another issue... One step at a time!