Non-stop inferior control.

	Non-stop inferior control.

	* infrun.c (resume): In non-stop mode, always resume just one
	thread.
	(proceed): Don't call prepare_to_proceed in non-stop mode.
	(fetch_inferior_event): In non-stop mode, switch context before
	handling the event.
	(error_is_running, ensure_not_running): New.
	(handle_inferior_event): In non-stop mode: Mark only the event
	thread as stopped.  Require that the target module manages adding
	threads to the thread list.  Assert that there isn't a
	deferred_step_ptid set.  Don't switch to infwait_thread_hop_state.
	(normal_stop): Only mark not-running if inferior hasn't exited.
	In non-stop mode, only mark the event thread.

	* thread.c:Include "cli/cli-decode.h".
	(print_thread_info): Don't read from a running thread.
	Output "(running)" if thread is running.
	(switch_to_thread): Don't read stop_pc if thread is executing.
	(do_restore_current_thread_cleanup): Don't write to a running
	thread.
	(thread_apply_all_command): Don't read from a running thread.  In
	non-stop mode, do a full context-switch instead of just switching
	threads.
	(thread_apply_command): In non-stop mode, do a full context-switch
	instead of just switching threads.
	(do_captured_thread_select): Likewise.  Inform user if selected
	thread is running.
	(_initialize_thread): Mark "info threads" and "thread" and
	async_ok.

	* inf-loop.c (inferior_event_handler): In non-stop mode, don't
	unregister the target from the event loop.

	* infcmd.c (continue_command, step_1, jump_command)
	(signal_command): Ensure the selected thread isn't running.
	(interrupt_target_command): In non-stop mode, interrupt only the
	selected thread.

	* inferior.h (error_is_running, ensure_not_running): Declare.

	* target.h (struct target_ops): Add ptid argument to the to_stop
	member.
	(target_stop): Add ptid_t argument.

	* target.c (update_current_target): Add ptid argument to to_stop's
	type.
	(debug_to_stop): Add ptid_t argument.
	(debug_to_rcmd): Set to_stop_ptid.

	* remote.c (remote_stop): Add ptid_t argument.
	(async_remote_interrupt): Add inferior_ptid to target_stop.
	* inf-ptrace.c (inf_ptrace_stop): Add ptid argument.

	* Makefile.in (thread.o): Depend on $(cli_decode_h).