ada: Implement inheritance of user-defined literal aspects for untagged types

ada: Implement inheritance of user-defined literal aspects for untagged types

In Ada 2022, user-defined literal aspects are nonoverridable but the named
subprograms present in them can be overridden, including for untagged types.

gcc/ada/

	* sem_res.adb (Has_Applicable_User_Defined_Literal): Apply the
	same processing for derived untagged types as for tagged types.
	* sem_util.ads (Corresponding_Primitive_Op): Adjust description.
	* sem_util.adb (Corresponding_Primitive_Op): Handle untagged
	types.