ada: Child unit subprograms are not primitive subprograms

ada: Child unit subprograms are not primitive subprograms

If a package declares a type and a child unit of that package is a subprogram
with a parameter (or function result) of that type, then that subprogram is
not a primitive subprogram of that type. Previously this was handled
incorrectly in some cases, leading to incorrect analysis of overriding
indicators.

gcc/ada/ChangeLog:

	* sem_util.adb (Collect_Primitive_Operations): When collecting
	primitive operations, do not include child unit subprograms.