Fix fcvt to only show 'ndigit' past decimal

Even if the number is really small and this means showing *no* digits.
This makes newlib match glibc, and the fcvt posix man page.

Signed-off-by: Keith Packard <keithp@keithp.com>

newlib/libc/stdlib/ecvtbuf.c

@@ -235,14 +235,7 @@ fcvtbuf (double invalue,
 
   save = fcvt_buf;
 
-  if (invalue < 1.0 && invalue > -1.0)
-    {
-      p = _dtoa_r (reent, invalue, 2, ndigit, decpt, sign, &end);
-    }
-  else
-    {
-      p = _dtoa_r (reent, invalue, 3, ndigit, decpt, sign, &end);
-    }
+  p = _dtoa_r (reent, invalue, 3, ndigit, decpt, sign, &end);
 
   /* Now copy */