pthread_stop_world.c (GC_suspend_handler): Redirect to suspension routine if signal is received and thread is flagged...

        * pthread_stop_world.c (GC_suspend_handler): Redirect to suspension
        routine if signal is received and thread is flagged SUSPENDED.
        (suspend_self): New function.
        (GC_suspend_thread): New function.
        (GC_resume_thread): New function.
        * include/gc.h (GC_suspend_thread): Declare.
        (GC_resumet_thread): Declare.
        * include/private/pthread_support.h (SUSPENDED): New GC_thread
        flag.

From-SVN: r114869