[Ada] Fix elaboration of record with 1-element dynamic array

[Ada] Fix elaboration of record with 1-element dynamic array

2018-12-11  Eric Botcazou  <ebotcazou@adacore.com>

gcc/ada/

	* einfo.ads (Is_Bit_Packed_Array): Fix values of component size.
	(Is_Packed): Likewise.
	* gcc-interface/utils.c (convert): Do not extract the value of a
	justified modular type if the destination type is a regular
	array.
	* gcc-interface/decl.c (gnat_to_gnu_component_type): Pass
	TYPE_DECL to validate_size wherever the array has packed
	components.

From-SVN: r267005