Rollup merge of #106232 - maurer:transparent-subst, r=rcvalle

CFI: Monomorphize transparent ADTs before typeid

Monomorphise `#[repr(transparent)]` parameterized ADTs before turning them into an Itanium mangled String.

`#[repr(transparent)]` ADTs currently use the single field to represent them in their CFI type ID to ensure that they are compatible. However, if that type involves a type parameter instantiated at the ADT level, as in `ManuallyDrop`, this will currently ICE as the `Parameter` type cannot be mangled. Since this happens at lowering time, it should always be concrete after substitution.

Fixes #106230