linuxthreads fixes from Will Newton (will.newton AT gmail.com):

linuxthreads fixes from Will Newton (will.newton AT gmail.com):
* share Sys V semaphores in order to get appropriate SEM_UNDO semantics.
* correct guardaddr in pthread_free() for TLS case
* move spinlock unlocking before restart()
* When exit was called from a signal handler, the restart
  from the manager processing the exit request instead restarted the thread
  in pthread_cond_timedwait.
  (see http://sources.redhat.com/ml/libc-ports/2006-05/msg00000.html)