Rebase symbiflow branch on current upstream master

[acomodi]

The symbiflow branch contains changes needed for FPGA-tool-perf. These changes will need to be pushed upstream, but for now we need to make sure everything is up-to-date with the current upstream master.

[kowalewskijan]

I'll take over this issue - we need to upstream the symbiflow branch as we want to add fpga-interchange variant.