[Ada] Fix expansion of aggregates components rewritten to raise statements

[Ada] Fix expansion of aggregates components rewritten to raise statements

2018-07-17  Ed Schonberg  <schonberg@adacore.com>

gcc/ada/

	* exp_aggr.adb (Component_OK_For_Backend): If an array component of the
	enclosing record has a bound that is out of range (and that has been
	rewritten as a raise statement) the aggregate is not OK for any back
	end, and should be expanded into individual assignments.

From-SVN: r262800