Fix ICE on invalid const param types
Fixes ICE #123863 which occurs because the const param has a type which is not a `bool`, `char` or an integral type.
The ICEing code path begins here in `typeck_with_fallback`: cb3752d20e/compiler/rustc_hir_typeck/src/lib.rs (L167)
The `fallback` invokes the `type_of` query and that eventually ends up calling `ct_infer` from the lowering code over here:
cb3752d20e/compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs (L561) and `ct_infer` ICEs at this location: cb3752d20e/compiler/rustc_hir_analysis/src/collect.rs (L392)
To fix the ICE it I'm triggering a `span_delayed_bug` before we hit `ct_infer` if the type of the const param is not one of the supported types
### Edit
On `@lcnr's` suggestion I've changed the approach to not let `ReStatic` region hit the `bug!` in `ct_infer` instead of triggering a `span_delayed_bug`.
aeb4c0413c