ada: Spurious predicate check at default initialization

ada: Spurious predicate check at default initialization

For an object created by an object_declaration with no explicit
initialization expression, if the type of the object is a record
type (or a private record type) with no components and a dynamic
predicate, then no predicate check must be performed at runtime
(RM 3.2.4(31/5)).

gcc/ada/ChangeLog:

	* sem_util.adb (Is_Partially_Initialized_Type): Return False
	for record types with no components.