* sem_ch3.adb (Array_Type_Declaration): move test for type in ALFA
after index creation; mark unconstrained base array type generated as
being in/not in ALFA as well
(Make_Index): mark subtype created as in/not in ALFA
* sem_ch5.adb (Analyze_Iteration_Scheme): mark entity for iterating
over a loop as in/not in ALFA, depending on its type and form of loop
iteration.