Fix int/EMACS_INT use in xdisp.c and print.c.

Fix int/EMACS_INT use in xdisp.c and print.c.

 print.c (print_object): Fix format string and argument types for
 printing a Lisp_Misc_Marker.
 xdisp.c (pos_visible_p, c_string_pos, number_of_chars)
 (load_overlay_strings, get_overlay_strings_1)
 (get_overlay_strings, forward_to_next_line_start)
 (back_to_previous_visible_line_start, reseat, reseat_to_string)
 (get_next_display_element, next_element_from_string)
 (next_element_from_c_string, next_element_from_buffer)
 (move_it_vertically_backward, move_it_by_lines, add_to_log)
 (message_dolog, message_log_check_duplicate, message2_nolog)
 (message3, message3_nolog, vmessage, set_message, set_message_1)
 (hscroll_window_tree, text_outside_line_unchanged_p)
 (set_cursor_from_row, set_vertical_scroll_bar, redisplay_window)
 (find_last_unchanged_at_beg_row)
 (find_first_unchanged_at_end_row, row_containing_pos)
 (trailing_whitespace_p, display_mode_element, decode_mode_spec)
 (display_count_lines, x_produce_glyphs, note_mouse_highlight): Use
 EMACS_INT for buffer and string positions.
 dispextern.h (struct it) <string_nchars>: Declare EMACS_INT.
 (row_containing_pos): Adjust prototype.
 lisp.h (pos_visible_p, message2, message2_nolog, message3)
 (message2_nolog, set_message): Adjust prototypes.