* lin-lwp.c (detach_callback): Don't call stop_wait_callback.

	* lin-lwp.c (detach_callback): Don't call stop_wait_callback.
	(stop_wait_callback): Handle !lp->signalled also.
	(lin_lwp_has_pending, flush_callback): New functions.
	(lin_lwp_wait): Call flush_callback.
	* linux-proc.c (linux_proc_add_line_to_sigset): New function.
	(linux_proc_pending_signals): New function.
	* linux-nat.h (linux_proc_pending_signals): Add prototype.