Bugzilla bug 362768: commented out the _pt_thread_death call in _PR_Fini

that was causing a hang on Mozilla shutdown.  It may not be safe to call
NSPR thread private data destructors in _PR_Fini.

nsprpub/pr/src/pthreads/ptthread.c

@@ -987,7 +987,9 @@ static void _PR_Fini(void)
     _PT_PTHREAD_GETSPECIFIC(pt_book.key, thred);
     if (NULL != thred)
     {
+#if 0  /* see bug 362768 comment 14 */
         _pt_thread_death(thred);
+#endif
         rv = pthread_setspecific(pt_book.key, NULL);
         PR_ASSERT(0 == rv);
     }