Typeable App pattern doesn't match function types

Consider the type representation,

rep = typeRep @(Int -> Char)

We would expect this to match the pattern,

(App (App arrowRep intRep) charRep)

where

arrowRep :: TypeRep ((->) :: Type -> Type -> Type)
intRep   :: TypeRep Int
charRep  :: TypeRep Char

However, this is currently not the case. Fix this.