Auto merge of #91743 - cjgillot:enable_mir_inlining_inline_all, r=oli-obk

Enable MIR inlining

Continuation of https://github.com/rust-lang/rust/pull/82280 by `@wesleywiser.`

#82280 has shown nice compile time wins could be obtained by enabling MIR inlining.
Most of the issues in https://github.com/rust-lang/rust/issues/81567 are now fixed,
except the interaction with polymorphization which is worked around specifically.

I believe we can proceed with enabling MIR inlining in the near future
(preferably just after beta branching, in case we discover new issues).

Steps before merging:
- [x] figure out the interaction with polymorphization;
- [x] figure out how miri should deal with extern types;
- [x] silence the extra arithmetic overflow warnings;
- [x] remove the codegen fulfilment ICE;
- [x] remove the type normalization ICEs while compiling nalgebra;
- [ ] tweak the inlining threshold.

compiler/rustc_const_eval/src/interpret/cast.rs

@@ -100,7 +100,8 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                             def_id,
                             substs,
                             ty::ClosureKind::FnOnce,
-                        );
+                        )
+                        .ok_or_else(|| err_inval!(TooGeneric))?;
                         let fn_ptr = self.create_fn_alloc_ptr(FnVal::Instance(instance));
                         self.write_pointer(fn_ptr, dest)?;
                     }