sysvsem module: release_sysvsem_sem and lockup(semaphore leak)

Since release_sysvsem_sem has error message while releasing acquired semaphores (both PHP_4_4 and PHP_5_1), it may end up with semaphore leak when error handler is used. The error message is useful for debugging, so the error message output should be configurable with ini setting. Although this workaround is not perfect solution, but it works in most cases. If there isn't a better idea, I'll add new ini directive to the module. -- Yasuo Ohgaki