Fix missing dtor calls for temp vars related to TYPEINI trees

In various places where symbAddTempVar() was used to create UDT temp vars,
the astDtorListAdd() call was missing.

Also, astTypeIniClone() (or rather its helper hRelinkTemps()) was not
adding the cloned temp vars via astDtorListAdd().

For param initializers, the sequence now is:
1. Parsing:
- parse expression via cInitializer()
- remove any registered temp var dtor calls via astDtorListClear()
- remember the expression in the PARAM symbol

2. "Instantiation":
- whenever the initializer expression is needed, clone it via
  astTypeIniClone()
- which duplicates all the temp vars into the current scope context
- and now also re-adds their dtor calls