i2c: arb: gpio-challenge: stop double error reporting

i2c_mux_add_adapter already logs a message on failure.

Reviewed-by: Wolfram Sang <[e-mail]>
Signed-off-by: Peter Rosin <[e-mail]>

drivers/i2c/muxes/i2c-arb-gpio-challenge.c

···
 
 	/* Actually add the mux adapter */
 	ret = i2c_mux_add_adapter(muxc, 0, 0, 0);
-	if (ret) {
-		dev_err(dev, "Failed to add adapter\n");
+	if (ret)
 		i2c_put_adapter(muxc->parent);
-	}
 
 	return ret;
 }