Remove __nacl_futex_fini

sysdeps/nacl/futex_emulation.c

 #include <futex_emulation.h>
 
 #include <assert.h>
 #include <errno.h>
 #include <irt_syscalls.h>
 #include <tls.h>
 
 
 static int global_futex_emulation_mutex_desc = -1;
 static LIST_HEAD (waiters_list);
 
 void __nacl_futex_init (void)
 {
   assert (global_futex_emulation_mutex_desc == -1);
   __nacl_irt_mutex_create (&global_futex_emulation_mutex_desc);
 }
 
-void __nacl_futex_fini (void)
-{
-  __nacl_irt_mutex_destroy (global_futex_emulation_mutex_desc);
-}
-
 int __nacl_futex_wait (volatile int *addr, int val, unsigned int bitset,
                        const struct timespec *timeout)
 {
   int retcode = -EINTR;
 
   if (__nacl_irt_mutex_lock (global_futex_emulation_mutex_desc))
     goto ret_no_unlock;
 
   if (*addr != val)
     {
@@ skipping 253 matching lines @@
       __nacl_irt_mutex_unlock (global_futex_emulation_mutex_desc);
       return retcode;
     }
 
 ret_unlock:
   if (!__nacl_irt_mutex_unlock (global_futex_emulation_mutex_desc))
     retcode = 0;
 ret_no_unlock:
   return retcode;
 }