update reference to the lifted lambda

Author: KisaragiEffective

src/Optimizations/GHC_opt/lambda_lifting.rst

@@ -37,7 +37,7 @@ Thus |glift| turns into:
 .. code-block:: haskell
 
    g_lifted a 0 = a
-   g_lifted a n = 1 + g (n - 1)
+   g_lifted a n = 1 + g_lifted (n - 1)
 
 Now ``a`` is an input, which means that |glift| can be floated out of ``f``
 to the top level producing the final program:
@@ -46,7 +46,7 @@ to the top level producing the final program:
 
    g :: Int -> Int -> Int
    g_lifted a 0 = a
-   g_lifted a n = 1 + g (n - 1)
+   g_lifted a n = 1 + g_lifted (n - 1)
 
    f :: Int -> Int -> Int
    f a 0 = a