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

*** 126,136 ****
              sizeof (tnf_bufsize)) != sizeof (tnf_bufsize)) {
                  (void) fprintf(stderr, gettext(
                          "kvm_read error in %s\n"), dumpfile);
                  exit(1);
          }
!         if (dump_bufaddr == NULL || tnf_bufsize == 0) {
                  (void) fprintf(stderr, gettext(
                          "No trace data available in the kernel.\n"));
                  exit(1);
          }
  }
--- 126,136 ----
              sizeof (tnf_bufsize)) != sizeof (tnf_bufsize)) {
                  (void) fprintf(stderr, gettext(
                          "kvm_read error in %s\n"), dumpfile);
                  exit(1);
          }
!         if (dump_bufaddr == (uintptr_t)NULL || tnf_bufsize == 0) {
                  (void) fprintf(stderr, gettext(
                          "No trace data available in the kernel.\n"));
                  exit(1);
          }
  }