* linux-low.c (PTRACE_GETSIGINFO, PTRACE_SETSIGINFO): Define.

	* linux-low.c (PTRACE_GETSIGINFO, PTRACE_SETSIGINFO): Define.
	(linux_resume_one_process): Take a siginfo_t *.  Update all
	callers.  Queue it if necessary.  Use PTRACE_SETSIGINFO.
	(struct pending_signals): Add a siginfo_t.
	(linux_wait_for_process): Always set last_status.
	(linux_wait_for_event): Use PTRACE_GETSIGINFO.
	(linux_queue_one_thread): Use PTRACE_GETSIGINFO.
	* linux-low.h (struct process_info): Add last_status.