ada: Fix alignment violation for chain of aligned and misaligned composite types

ada: Fix alignment violation for chain of aligned and misaligned composite types

This happens when aggressive optimizations are enabled (i.e. -O2 and above)
because the ivopts pass fails to properly mark the new memory accesses it is
creating as misaligned by means of the build_aligned_type function.

gcc/ada/ChangeLog:

	* gcc-interface/utils.cc (make_packable_type): Clear the TYPE_PACKED
	flag in the case where the alignment is bumped.