Auto merge of #102340 - JakobDegen:pass-manager-simplification, r=oli-obk

Split phase change from `MirPass`

The main goal here is to simplify the pass manager logic. `MirPass` no longer contains the `phase_change` method, and `run_passes` instead accepts an `Option<PhaseChange>`. The hope is that this addresses the comments (and maybe perf regression) from #99102 .

r? `@oli-obk` cc `@RalfJung`

compiler/rustc_const_eval/src/transform/promote_consts.rs

@@ -41,10 +41,6 @@ pub struct PromoteTemps<'tcx> {
 }
 
 impl<'tcx> MirPass<'tcx> for PromoteTemps<'tcx> {
-    fn phase_change(&self) -> Option<MirPhase> {
-        Some(MirPhase::Analysis(AnalysisPhase::Initial))
-    }
-
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
         // There's not really any point in promoting errorful MIR.
         //