Remove a dead branch in integerDec

If the absolute value of the input is small enough to enter this
branch, then it fits in an Int and takes the very first branch instead.

Data/ByteString/Builder/ASCII.hs

@@ -275,10 +275,8 @@ integerDec i
     | otherwise =                                   go i
   where
     go :: Integer -> Builder
-    go n | n < maxPow10 = intDec (fromInteger n)
-         | otherwise    =
-             case putH (splitf (maxPow10 * maxPow10) n) of
-               x:|xs -> intDec x `mappend` P.primMapListBounded intDecPadded xs
+    go n = case putH (splitf (maxPow10 * maxPow10) n) of
+             x:|xs -> intDec x `mappend` P.primMapListBounded intDecPadded xs
 
     splitf :: Integer -> Integer -> NonEmpty Integer
     splitf pow10 n0