3772 consider raising default descriptor soft limit

@@ -101,11 +101,13 @@
 extern int      svc_ndoorfds;
 extern SVCXPRT_LIST *_svc_xprtlist;
 extern mutex_t xprtlist_lock;
 extern void __svc_rm_from_xlist();
 
+#if !defined(_LP64)
 extern fd_set _new_svc_fdset;
+#endif
 
 /*
  * If the allocated array of reactor is too small, this value is used as a
  * margin. This reduces the number of allocations.
  */