Allocate data in cached_reg_t

2017-01-18  Alan Hayward  <alan.hayward@arm.com>

	* remote.c (struct cached_reg): Change data into a pointer.
	* (stop_reply_dtr): Free data pointers before deleting vector.
	(process_stop_reply): Likewise.
	(remote_parse_stop_reply): Allocate space for data