* Remove no-std code for cranelift_codegen::timings
no-std mode isn't supported by Cranelift anymore
* Simplify define_passes macro
* Add egraph opt timings
* Replace the add_to_current api with PassTimes::add
* Omit a couple of unused time measurements
* Reduce divergence between run and run_passes a bit
* Introduce a Profiler trait
This allows plugging in external profilers into the Cranelift profiling
framework.
* Add Pass::description method
* Remove duplicate usage of the compile pass timing
* Rustfmt
