20240718
  dtoa.c:  Tweak the change of 20240715 to fix a bug that caused dtoa
to render 6.9999999999999996e-161 as 7e-161 to allow more efficiency
in some cases:  change
	if (!(zb & ures) && (ures-rb) << (1 - eulp) < ulp)
		goto Fast_failed1;
to
	if (!(zb & ures) && (ures-rb) << (1 - eulp) < ulp) {
		if ((ures + rb) << (2 - eulp) < ulp)
			goto Roundup;
		goto Fast_failed1;
		}