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

*** 245,255 ****
          err.dteda_pdesc = errpd;
          err.dteda_cpu = data->dtpda_cpu;
          err.dteda_action = -1;
          err.dteda_offset = -1;
          err.dteda_fault = DTRACEFLT_LIBRARY;
!         err.dteda_addr = NULL;
  
          len = strlen(faultstr) +
              strlen(errpd->dtpd_provider) + strlen(errpd->dtpd_mod) +
              strlen(errpd->dtpd_name) + strlen(errpd->dtpd_func) +
              slop;
--- 245,255 ----
          err.dteda_pdesc = errpd;
          err.dteda_cpu = data->dtpda_cpu;
          err.dteda_action = -1;
          err.dteda_offset = -1;
          err.dteda_fault = DTRACEFLT_LIBRARY;
!         err.dteda_addr = 0L;
  
          len = strlen(faultstr) +
              strlen(errpd->dtpd_provider) + strlen(errpd->dtpd_mod) +
              strlen(errpd->dtpd_name) + strlen(errpd->dtpd_func) +
              slop;