Fix an issue caused by an incorrect type construcion.

The tuple _value_ constructor was being used instead of the
tuple _type_ constructor, which was causing an ill-typed
term to be emitted.

Fixes #1119

src/SAWScript/Crucible/LLVM/Override.hs

@@ -1231,7 +1231,7 @@ typeToSC sc t =
          scVecType sc n ty'
     Crucible.Struct fields ->
       do fields' <- V.toList <$> traverse (typeToSC sc . view Crucible.fieldVal) fields
-         scTuple sc fields'
+         scTupleType sc fields'
 
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