tree-data-ref.c (struct data_ref_loc_d): Replace pos field with ref.

	* tree-data-ref.c (struct data_ref_loc_d): Replace pos field with ref.
	(get_references_in_stmt): Don't record operand addresses, but
	operands themselves.
	(find_data_references_in_stmt, graphite_find_data_references_in_stmt):
	Adjust for the pos -> ref change.

From-SVN: r205760