testing/yosys: upgrade to 0.42
testing/yosys: upgrade to 0.42
https://github.com/YosysHQ/yosys/releases/tag/yosys-0.42
Note: This failed to link with clang/LLVM, but worked out of the box with GCC. So, I just changed the toolchain to GCC.
Also note: The unit test segfaulted with LTO. Hence, LTO was disabled.
community/iverilog: enable FST support
Add missing zlib-dev to makedepends to enable FST support. This is needed to pass the unit tests of yosys.