Remove deprecated function copilot-language:Copilot.Language.Operators.Extern.funArg. Refs #250.

The function copilot-language:Copilot.Language.Operators.Extern.funArg
was deprecated since Copilot 3.3.

As we reach 3 versions without detecting any need for it from any
internal or external work, this function is now ready to be removed.

Author: ivanperez-keera

copilot-language/src/Copilot/Language/Operators/Extern.hs

@@ -18,7 +18,6 @@ module Copilot.Language.Operators.Extern
   , externI32
   , externI64
   , externD
-  , funArg
   ) where
 
 import Copilot.Core (Typed)
@@ -42,11 +41,6 @@ extern :: Typed a
        -> Stream a
 extern = Extern
 
--- | Deprecated.
-funArg :: Typed a => Stream a -> Arg
-funArg = Arg
-{-# DEPRECATED funArg "funArg is deprecated" #-}
-
 --------------------------------------------------------------------------------
 
 -- | Create a stream carrying values of type Bool, populated by an external