5218 posix definition of NULL
correct unistd.h and iso/stddef_iso.h
update gate source affected

*** 85,95 ****
          uintptr_t       baseaddr;
          uintptr_t       dentry_addr;
          Elf3264_Dyn     *dynam_tab = NULL;
          long            dynam_tab_size;
  
!         *entaddr_p = NULL;
  
          prbstat = prb_mainobj_get(hndl->proc_p, &objfd, &baseaddr);
          if (prbstat)
                  return (_tnfctl_map_to_errcode(prbstat));
  
--- 85,95 ----
          uintptr_t       baseaddr;
          uintptr_t       dentry_addr;
          Elf3264_Dyn     *dynam_tab = NULL;
          long            dynam_tab_size;
  
!         *entaddr_p = (uintptr_t)NULL;
  
          prbstat = prb_mainobj_get(hndl->proc_p, &objfd, &baseaddr);
          if (prbstat)
                  return (_tnfctl_map_to_errcode(prbstat));