Remove an unused function

This is not used, as we need a more complex serialisation, which is
done in the saveObjectField function.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Agata Murawska <agatamurawska@google.com>

htools/Ganeti/THH.hs

@@ -146,10 +146,6 @@ loadFn (Field { fieldIsContainer = True }) expr = [| $expr >>= readContainer |]
 loadFn (Field { fieldRead = Just readfn }) expr = [| $expr >>= $readfn |]
 loadFn _ expr = expr
 
-saveFn :: Field -> Q Exp -> Q Exp
-saveFn (Field { fieldIsContainer = True }) expr = [| showContainer $expr |]
-saveFn (Field { fieldRead = Just readfn }) expr = [| $readfn $expr |]
-saveFn _ expr = expr
 
 -- * Common field declarations