-trunc* bug - don't increase yweaks in this case


myisam/ft_boolean_search.c:
  -trunc* bug - don't increase yweaks in this case
mysql-test/r/fulltext.result:
  -trunc* bug - don't increase yweaks in this case
mysql-test/t/fulltext.test:
  -trunc* bug - don't increase yweaks in this case