ada: Check default value aspects before resolving their expressions

ada: Check default value aspects before resolving their expressions

Check expressions of aspects Default_Value and Default_Component_Value
for references to the annotated types just before resolving these
expressions.

This patch fixes both an asymmetry in processing of those aspects and
adds a missing check in GNATprove on aspect Default_Component_Value.

gcc/ada/

	* sem_ch13.adb (Check_Aspect_Too_Late): Move routine to top-level.
	(Resolve_Aspect_Expressions): Check aspects Default_Value and
	Default_Component_Value before resolving their expressions.