Use the cabal configuration flags where possible when finalizing the PackageDescription.

Language/Haskell/GhcMod/Debug.hs

@@ -31,7 +31,7 @@ debugInfo = cradle >>= \c -> convert' =<< do
     simpleCompilerOption = options >>= \op ->
         return $ CompilerOptions (ghcUserOptions op) [] []
     fromCabalFile c = options >>= \opts -> do
-        pkgDesc <- parseCabalFile $ fromJust $ cradleCabalFile c
+        pkgDesc <- parseCabalFile c $ fromJust $ cradleCabalFile c
         getCompilerOptions (ghcUserOptions opts) c pkgDesc
 
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