(XTflash): Use pointers as args to select.

(XTflash): Use pointers as args to select.
(XTread_socket, x_set_offset, x_set_window_size)
(x_make_frame_invisible): Cast 2nd arg to x_wm_set_size_hint.
(XTclear_end_of_line): Don't specify return type.
(note_mouse_highlight): Declare args x and y.
(x_icon_type): New declaration.
(flashback): Declaration deleted.