Some 32,000 officers will be assigned to the Feb. 24 funeral of Emperor Hirohito to protect scores of foreign dignitaries and guard against potential terrorism in Japan's largest security task since World War II, police said Thursday. Heads of state and dignitaries from more than 100 countries - including George Bush, who succeeds President Reagan Jan. 20 - plan to attend the funeral in the capital for Hirohito, who died Saturday at age 87 after a lengthy battle against intestinal cancer.