Update lib/i2c/nil_backend.ex

Co-authored-by: Copilot <[email protected]>

Author: fhunleth

lib/i2c/nil_backend.ex

@@ -11,7 +11,7 @@ defmodule Circuits.I2C.NilBackend do
   alias Circuits.I2C.Backend
   alias Circuits.I2C.Bus
 
-  defstruct [:empty]
+  defstruct []
 
   @doc """
   Return the I2C bus names on this system