Auto merge of #116144 - lcnr:subst-less, r=oli-obk

subst -> instantiate

continues #110793, there are still quite a few uses of `subst` and `substitute`, but changing them all in the same PR was a bit too much, so I've stopped here for now.

compiler/rustc_codegen_ssa/src/mir/mod.rs

@@ -118,7 +118,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         T: Copy + TypeFoldable<TyCtxt<'tcx>>,
     {
         debug!("monomorphize: self.instance={:?}", self.instance);
-        self.instance.subst_mir_and_normalize_erasing_regions(
+        self.instance.instantiate_mir_and_normalize_erasing_regions(
             self.cx.tcx(),
             ty::ParamEnv::reveal_all(),
             ty::EarlyBinder::bind(value),