ada: Fix list of attributes defined by Ada 2022

ada: Fix list of attributes defined by Ada 2022

Recognize references to attributes Put_Image and Object_Size as
language-defined in Ada 2022 and implementation-defined in earlier
versions of Ada. Other attributes listed in Ada 2022 RM, K.2 and
currently implemented in GNAT are correctly categorized.

This change only affects code with restriction
No_Implementation_Attributes.

gcc/ada/

	* sem_attr.adb (Attribute_22): Add Put_Image and Object_Size.
	* sem_attr.ads (Attribute_Impl_Def): Remove Object_Size.